Laboratory Testing Application Notes - NANOVEA: Advanced Profilometers, Tribometers, Nanoindenters, and Scratch Testers for Materials Testing

Non-Contact Profilometry of Soft and Transparent Materials

Andrew Shore — Wed, 09 Sep 2026 17:40:54 +0000

Application Note | Non-Contact 3D Profilometry

Non-Contact Profilometry of Soft and Transparent Materials

Comprehensive Characterization of Challenging Surfaces Without Contact, Deformation, or Sample Preparation

Research & Experimental Testing

크레이그 라이징

Visual Design & Editorial

앤드류 쇼어

소개

Soft, transparent, and easily deformable materials are increasingly important across advanced applications including flexible bioelectronics, wearable sensors, biomedical interfaces, microfluidic devices, and other polymer-based technologies. Characterizing these materials can be difficult because the measurement method itself may influence the surface or fail to capture it reliably.

Contact-based techniques can deform, scratch, or move soft materials during measurement, while transparent or absorptive surfaces can present additional challenges for some optical techniques. Non-contact profilometry avoids physical interaction with the sample while enabling quantitative surface characterization across challenging material types.

In this study, an extremely soft and translucent petroleum-jelly-based material was selected as a demanding proof-of-concept sample. Using the NANOVEA ST400 Profilometer, the surface was characterized without physical contact or sample preparation to demonstrate the broader capability of non-contact profilometry for delicate and difficult-to-measure materials.

The Advantage of Non-Contact Profilometry for Challenging Materials

Soft materials can be difficult to measure accurately because physical contact may alter the surface during the measurement itself. Films, gels, and other compliant materials can deform, scratch, or move under a contacting probe, potentially changing the geometry being characterized.

Transparent and absorptive surfaces can introduce additional measurement challenges for some optical techniques, including effects associated with light transmission, absorption, and internal reflections. NANOVEA Non-Contact Profilometers use axial chromatism to determine surface height without physically contacting the sample.

This combination enables quantitative characterization of challenging surfaces while minimizing measurement influence. Depending on the application, measurements can include surface roughness, flatness, 3D topography, surface area, profile geometry, and other dimensional characteristics without requiring sample preparation.

측정 목표

The objective of this study was to demonstrate non-contact surface characterization on an extremely soft and translucent material, representing the type of measurement challenge encountered when a surface may be altered by physical contact or prove difficult for some optical techniques.

A petroleum-jelly-based lip balm was selected as a deliberately challenging proof-of-concept sample because of its softness and translucency. The sample was measured using the NANOVEA ST400 Profilometer without physical contact or sample preparation.

The resulting measurement was used to obtain 3D topography, 2D profile data, surface roughness, flatness, and 3D surface area, demonstrating the range of quantitative surface information that can be obtained from a delicate material using non-contact profilometry.

나노비아 ST400 Non-Contact

광학 프로파일로미터

Optical Profilometry Results

Soft, translucent petroleum-jelly-based sample used for non-contact profilometry.

The sample being scanned by the NANOVEA ST400 for non-contact surface measurement.

3D Profile Measurement

The NANOVEA ST400 captured the 3D surface of the extremely soft and translucent sample without physically contacting the material. The resulting topography was used to evaluate multiple aspects of the surface, including ISO 25178 surface parameters, 3D surface area, and flatness corresponding to ISO 12781. A 2D cross-section was also extracted from the measurement to provide additional profile detail.

Obtaining these measurements from such a soft and translucent surface demonstrates the value of non-contact profilometry for materials that could otherwise be altered by a contacting probe or present challenges for some optical techniques. Quantitative surface geometry can be acquired while preserving the condition of the measured surface.

3D surface profile of the soft, transparent sample with ISO 25178 surface parameters and flatness analysis.

2D Profile Measurement

2D profile extracted from the non-contact 3D surface measurement across a 4 mm section of the sample.

An intensity/contrast image was also acquired simultaneously with the 3D surface measurement, providing complementary visual information alongside the measured topography.

False-color height map showing surface height variation across the soft, translucent sample.

Intensity image acquired simultaneously with the 3D surface measurement.

결론

This study demonstrates how non-contact profilometry can characterize surfaces that combine two particularly difficult measurement conditions: extreme softness and translucency. Using the NANOVEA ST400, quantitative 3D surface data were acquired without physically contacting or preparing the sample.

A petroleum-jelly-based lip balm was selected as a deliberately challenging proof-of-concept material rather than as the end application itself. Its soft, translucent surface provided a practical demonstration of the ability to obtain surface roughness, flatness, 3D surface area, profile geometry, and complementary intensity data while minimizing the influence of the measurement process on the surface.

This capability is relevant wherever delicate, compliant, transparent, or absorptive materials must be characterized without deformation or surface damage. As soft polymers, gels, transparent elastomers, and related materials continue to appear in areas such as biomedical interfaces, wearable technologies, microfluidics, and advanced polymer systems, non-contact surface measurement provides a useful approach for evaluating their surface geometry and topography.

Frequently Asked Questions About Non-Contact Profilometry

Why is non-contact profilometry useful for soft materials?

Soft materials can deform, scratch, or move when touched by a contacting probe. Non-contact profilometry measures the surface optically, reducing the risk that the measurement itself alters the geometry being characterized.

Can non-contact profilometry measure transparent materials?

Yes, depending on the optical technology and material. NANOVEA profilometers use axial chromatism to determine surface height and can characterize transparent, opaque, specular, diffusive, polished, and rough surfaces without physical contact.

Can soft and transparent surfaces be measured without sample preparation?

In this study, the soft and transparent petroleum-jelly-based sample was measured without sample preparation. Avoiding coatings or other surface modification can be especially valuable when the original surface condition needs to be preserved.

What can be measured with non-contact 3D profilometry?

Non-contact 3D profilometry can provide quantitative measurements including surface roughness, 3D topography, flatness, surface area, 2D profiles, and other dimensional characteristics, depending on the measurement objective and surface geometry.

What types of materials benefit from non-contact surface measurement?

Non-contact measurement is especially useful for materials that are soft, delicate, transparent, semi-transparent, easily scratched, or otherwise difficult to probe physically. It can also be useful when maintaining the original surface condition is important.

How is non-contact profilometry different from contact profilometry?

Contact profilometry uses a physical stylus that moves across the surface. Non-contact profilometry acquires surface height optically, eliminating probe-to-sample contact and reducing the possibility of contact-induced deformation, scratching, or movement on sensitive materials.

Need Reliable Non-Contact Surface Characterization?

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Humidity-Controlled Nanoindentation of Polymer Materials

Andrew Shore — Wed, 02 Sep 2026 21:48:17 +0000

Application Note | Environmental Nanoindentation

Humidity-Controlled Nanoindentation of Polymer Films

Measuring Hardness and Creep Under Controlled Relative Humidity

Research & Experimental Testing

Duanjie Li, PhD & Andrea Novitsky

Visual Design & Editorial

앤드류 쇼어

소개

Polymers are viscoelastic materials, meaning their mechanical response can change with time and environmental conditions. Under sustained loading, they can gradually deform through creep, with the rate of deformation influenced by factors such as material properties, exposure time, temperature, and humidity.

As environmental humidity changes, the mechanical behavior of polymer materials can change as well. Measuring hardness and creep under controlled relative humidity provides a quantitative way to evaluate how moisture exposure affects polymer performance.

Why Humidity-Controlled Nanoindentation Matters

The mechanical properties of polymers can change as environmental humidity increases. As moisture is absorbed, polymers may exhibit mechano-sorptive effects, including accelerated creep and changes in deformation behavior under load.

Reliable characterization therefore requires more than measuring the material at a single ambient condition. Humidity-controlled nanoindentation enables hardness and creep to be measured while both the sample and indenter are maintained in a uniform controlled environment.

The NANOVEA Mechanical Tester uses an isolated humidity enclosure around the indentation tip and sample surface to maintain consistent relative humidity during testing. This helps minimize measurement drift caused by humidity gradients and provides a quantitative way to evaluate moisture-dependent mechanical behavior.

측정 목표

The objective of this study was to evaluate how controlled relative humidity influences the hardness and creep behavior of a polymer film using 나노 인덴테이션.

The polymer film was tested in an isolated environment with uniform humidity surrounding both the sample and indenter, allowing its mechanical response to be measured under controlled moisture conditions.

나노비아 PB1000 Advanced

기계 테스터

테스트 조건

A polymer film was tested by nanoindentation at 25, 35, 45, 55, 65, and 75% relative humidity. Both the sample and indenter were maintained inside an isolated enclosure with uniform humidity controlled throughout the test.

Polymer film sample used for humidity-controlled nanoindentation testing.

A Berkovich diamond indenter was used with a maximum load of 10 mN. The load was applied and removed at 20 mN/min, and creep was measured from the change in indentation depth during a 10 s hold at maximum load.

Hardness was calculated using ASTM E2546 and the Oliver & Pharr method. The test conditions are summarized below.

Humidity (%)	25, 35, 45, 55, 65, 75
Maximum load	10mN
로딩 속도	20mN/min
Unloading rate	20mN/min
Creep time	10 s
Computation method	ASTM E2546 & Oliver & Pharr
Indenter type	Berkovich diamond

결과 및 토론

The load-displacement curves show a progressive increase in penetration depth as relative humidity rises, indicating that the polymer film becomes more susceptible to deformation under the same applied load.

Between 25% and 55% relative humidity, hardness decreased gradually from approximately 0.60 to 0.54 GPa, while creep depth increased from 36 to 48 nm. At higher humidity, the changes became substantially more pronounced. Hardness decreased to 0.46 GPa at 65% RH and 0.31 GPa at 75% RH, while creep depth increased to 80 nm and 105 nm, respectively.

The original study attributes this stronger response at elevated humidity to moisture absorption and swelling of the polymer film. It identifies the transition between 55% and 65% RH as the range where swelling becomes significant, corresponding with the sharp increase in creep observed during indentation.

These results demonstrate why humidity can be an important test variable when evaluating polymers intended for moisture-rich environments. Measuring both hardness and creep across controlled humidity levels provides a more complete view of how the material responds mechanically as environmental conditions change.

Nanoindentation load-displacement curves at relative humidity levels from 25% to 75%.

Polymer hardness decreases while creep depth increases as relative humidity rises from 25% to 75%.

결론

Humidity-controlled nanoindentation revealed a clear change in the mechanical response of the polymer film as relative humidity increased. Across the tested range from 25% to 75% RH, hardness progressively decreased while creep increased.

At 65% RH and above, the polymer exhibited substantially greater creep deformation during the hold at maximum load, corresponding with the sharper reduction in hardness observed at higher humidity.

By maintaining both the sample and indenter within an isolated environment of uniform relative humidity, the NANOVEA Mechanical Tester enables hardness and creep to be measured while minimizing the influence of humidity-gradient drift. This provides a quantitative method for evaluating the moisture-dependent mechanical behavior of polymer materials under controlled environmental conditions.

Frequently Asked Questions About Humidity-Controlled Nanoindentation

Why does humidity affect polymer hardness and creep?

Polymers can absorb moisture from the surrounding environment, which can alter their mechanical response. Depending on the material, increased moisture can reduce resistance to deformation and increase time-dependent creep. In this study, increasing relative humidity corresponded with decreasing hardness and increasing creep depth.

Can nanoindentation be performed under controlled humidity?

Yes. Nanoindentation can be performed inside a controlled environmental enclosure so that both the sample and indenter are exposed to a defined relative humidity during testing. This makes it possible to compare mechanical properties under different moisture conditions rather than relying solely on uncontrolled ambient laboratory conditions.

Why test polymers at controlled relative humidity instead of ambient conditions?

Ambient humidity can vary and may not represent the conditions a polymer experiences during storage, processing, or use. Controlling relative humidity allows the environmental condition to become a defined test variable, making it possible to determine whether changes in hardness, creep, or deformation behavior are associated with moisture exposure.

What mechanical properties can be measured under controlled humidity?

Depending on the test method, nanoindentation can evaluate properties including hardness, elastic modulus, and time-dependent creep behavior under controlled environmental conditions. In this study, hardness and creep were measured as relative humidity changed.

What materials can benefit from humidity-controlled nanoindentation?

Humidity-controlled testing can be particularly useful for polymers, thin films, coatings, and other materials whose mechanical behavior may be influenced by moisture absorption. The appropriate humidity range and indentation conditions depend on the material and application.

How can humidity-controlled nanoindentation support material development?

Testing across multiple relative humidity levels can reveal whether a material maintains its mechanical properties as environmental moisture changes. This can support material comparison, formulation development, coating evaluation, failure investigation, and the assessment of materials intended for humidity-sensitive applications.

Can NANOVEA perform humidity-controlled nanoindentation as a laboratory service?

Yes. NANOVEA can perform nanoindentation testing under controlled environmental conditions to evaluate properties such as hardness and creep as humidity changes. Test parameters can be selected according to the material, expected service conditions, and the specific engineering question being investigated.

Need Humidity-Controlled Nanoindentation for Your Material?

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High Temperature Brinell Hardness Testing

Andrew Shore — Thu, 20 Aug 2026 23:22:06 +0000

Application Note | High Temperature Mechanical Testing

High Temperature Hardness Testing of Steel Using Brinell Indentation

Mapping Steel Hardness Loss from Room Temperature to 925°C with NANOVEA T2000 Tribometer

Research & Experimental Testing

Frank Liu

Visual Design & Editorial

앤드류 쇼어

소개

High temperature hardness testing provides insight into how the mechanical behavior of metals changes as temperature increases. Materials that exhibit high hardness at room temperature can soften significantly when exposed to elevated temperatures, making temperature-dependent hardness an important consideration when selecting materials for applications such as jet engines, high-temperature processing equipment, and other thermally demanding environments.

In this study, a steel sample was evaluated using Brinell indentation with the NANOVEA T2000 Tribometer. Hardness measurements were performed at 25, 200, 400, 600, 800, and 925°C to map the change in steel hardness with temperature. The results show a gradual reduction in hardness through approximately 600°C, followed by a much sharper decline at higher temperatures, resulting in an 84% decrease in hardness between room temperature and 925°C.

Why High Temperature Hardness Testing Matters

Hardness is a mechanical property that describes a material’s resistance to localized deformation. Higher hardness generally corresponds to greater resistance to indentation and permanent surface deformation.

Temperature can significantly alter this behavior. A material that remains hard at room temperature may soften as temperature increases, changing its mechanical response under elevated-temperature conditions. For materials intended for high-temperature applications, understanding these changes is important when evaluating their mechanical limits.

High temperature hardness testing makes it possible to measure these changes directly as temperature increases rather than relying only on room-temperature properties. In this study, the steel sample provides a clear example of how hardness can remain relatively stable over part of the temperature range before declining rapidly at higher temperatures.

측정 목표

The objective of this study was to evaluate how the Brinell hardness of steel changes as temperature increases from room temperature to 925°C.

Using a 10 mm tungsten carbide (WC) ball, a load of 1000 N (~100 kgf) was applied to the steel sample at 25, 200, 400, 600, 800, and 925°C. The resulting indentations were measured using NANOVEA’s 3D Line Sensor to determine their diameter for Brinell hardness calculation.

나노비아 T2000 고부하

공압식 마찰계

테스트 절차

High temperature Brinell hardness testing was performed with the steel sample mounted inside the NANOVEA T2000 heated chamber. The sample was tested at six temperatures from 25°C to 925°C using a 10 mm tungsten carbide (WC) ball with an applied test force of 1000 N (~100 kgf).

The test parameters used throughout the study are summarized below.

Steel sample mounted in the NANOVEA T2000 high temperature chamber for Brinell hardness testing from 25°C to 925°C.

테스트 매개변수

Test Parameter	High Temperature Brinell Hardness Setup
온도	25, 200, 400, 600, 800, 925°C
Test force	1000 N (~100 kgf)
Force-diameter ratio	1
Ball material	Tungsten carbide (WC)
Ball diameter	10 mm

Steel samples used in the high temperature Brinell hardness study from room temperature to 925°C.

결과 및 토론

Brinell hardness was calculated from the applied force, ball diameter, and measured indentation diameter using the equation below:

Where F (kgf) is the applied force expressed in kilogram-force, D is the ball diameter, and d is the measured indentation diameter. Two diameter measurements were taken for each indent and averaged to determine the value of d used in the hardness calculation.

Load vs. time profile for the 1000 N Brinell indentations performed during high temperature hardness testing.

The loading curve shows the applied load profile used during indentation. A consistent 1000 N (~100 kgf) test force was used throughout the temperature series so that the resulting indentation dimensions and calculated hardness values could be compared across each test condition.

거리	Unit	A	B
HDist	mm	1.807	1.830

Brinell indentation measured at 800°C. Two diameter measurements of 1.807 mm and 1.830 mm were averaged to determine the indentation diameter used for hardness calculation.

At 800°C, the measured indentation diameters were 1.807 mm and 1.830 mm, producing an average diameter of approximately 1.819 mm. The indentation diameter increased substantially at the higher test temperatures as the steel became softer under the same applied load.

The measured indentation diameters were then used to calculate Brinell hardness at each temperature. The results show a relatively gradual decrease from 96.12 HBW at 25°C to 79.69 HBW at 600°C, followed by a much sharper decrease to 38.18 HBW at 800°C and 15.40 HBW at 925°C.

Brinell Hardness Results

Temperature (°C)	Diameter 1 (mm)	Diameter 2 (mm)	Average Diameter (mm)	HBW (10/100)
High Temperature Brinell Hardness Results
25	1.153	1.145	1.149	96.12
200	1.150	1.201	1.176	91.82
400	1.165	1.261	1.213	86.21
600	1.265	1.258	1.262	79.69
800	1.807	1.830	1.819	38.18
925	2.858	2.833	2.846	15.40

The temperature-dependent trend is clear. Steel hardness decreased moderately between room temperature and 600°C, then declined rapidly at higher temperatures. Between 25°C and 925°C, the measured Brinell hardness decreased from 96.12 to 15.40 HBW, representing an overall hardness loss of approximately 84%.

These results demonstrate why hardness measured at room temperature alone may not fully represent material behavior in high-temperature applications. For this steel sample, the most substantial loss in hardness occurred above approximately 600°C.

결론

High temperature hardness testing revealed a strong temperature-dependent change in the Brinell hardness of the steel sample. Hardness decreased gradually as temperature increased from 25°C to 600°C, then declined much more sharply at higher temperatures. By 925°C, the measured hardness had fallen from 96.12 HBW to 15.40 HBW, representing an overall decrease of approximately 84%.

The study demonstrates the ability of the NANOVEA T2000 Tribometer to perform Brinell hardness measurements under elevated-temperature conditions. Using a 1000 N (~100 kgf) test force, the steel sample was evaluated from 25°C to 925°C, allowing its change in hardness to be measured directly across the tested temperature range.

The results also highlight the importance of selecting an appropriate force-diameter ratio across a wide temperature range. Because of the large difference in hardness between room temperature and high temperature, the study recommends a force-diameter ratio of 5 or 10 at lower temperatures, while a ratio of 1 is suitable above 900°C.

Frequently Asked Questions About High Temperature Hardness Testing

What is high temperature hardness testing used for?

High temperature hardness testing evaluates how a material’s resistance to indentation changes as temperature increases. It is useful for materials intended for thermally demanding applications where room-temperature hardness may not represent mechanical behavior at operating temperature.

Can Brinell hardness be measured at elevated temperatures?

Yes. Elevated-temperature Brinell hardness testing applies a controlled force using a ball of known diameter while the specimen is heated to the required test temperature. In this study, steel was tested from 25°C to 925°C using a 10 mm tungsten carbide ball and a 1000 N test force.

Why measure hardness while the material is hot?

Testing at temperature measures hardness under the thermal condition of interest rather than only after the specimen returns to room temperature. This makes it possible to directly characterize temperature-dependent softening and identify changes that may not be represented by room-temperature hardness values.

What equipment is used for high temperature hardness testing?

High temperature hardness testing requires controlled specimen heating, precise mechanical loading and measurement of the resulting indentation. The NANOVEA T2000 can integrate high-temperature environmental control with mechanical testing for evaluating material behavior under elevated-temperature conditions.

Can high temperature hardness testing be used for aerospace materials?

Yes. Elevated-temperature hardness measurements are relevant when evaluating materials intended for thermally demanding aerospace environments, including jet-engine and other high-temperature components. Testing helps characterize how hardness changes as exposure temperature increases.

Can NANOVEA perform high temperature hardness testing as a laboratory service?

NANOVEA provides materials testing services using its mechanical testing and tribology platforms. Application requirements, temperature range, load, specimen geometry and measurement method can be reviewed with a NANOVEA applications engineer to determine an appropriate high-temperature testing approach.

Need High Temperature Hardness Testing for Your Material?

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Pacing Lead Insulation Wear Testing in Hanks’ Solution

Andrew Shore — Wed, 17 Jun 2026 17:55:24 +0000

Application Note | Medical Device Tribology

Nano-Friction and Wear Testing of Pacing Lead Insulation in Hanks’ Solution

Tribological analysis of silicone and polyether-polyurethane endocardial lead materials

Research & Experimental Testing

Duanjie Li, PhD

Visual Design & Editorial

앤드류 쇼어

소개

A pacemaker is a medical device used to regulate heart rhythm and maintain an adequate heart rate. It is typically implanted in the chest or abdomen and sends electrical impulses to the heart muscle through endocardial pacing leads.

As pacemakers remain a widely used treatment for cardiac rhythm disorders, the quality and service life of pacing leads are critical to long-term device performance. Lead failures can create serious risks for patients and may require surgical replacement, making pacing lead insulation wear testing an important part of material evaluation for implantable cardiac devices.^1–5

Endocardial pacing leads transmit electrical impulses from a pacemaker to the heart while operating in a dynamic body-fluid environment.

Why Friction and Wear Matter for Endocardial Lead Insulation

The outer insulation material of an endocardial lead requires several key properties, including biological inertness, high flexibility, fracture toughness, and long service life. Low friction can reduce interaction between the lead and the blood vessel, helping minimize vessel irritation during implantation and movement.

Wear resistance is also critical. Endocardial leads experience continuous movement from the heart and surrounding body structures, while operating in a body-fluid environment that can influence friction, wear, and material response.

Because of this complex environment, endocardial lead insulation should be evaluated using controlled tribological methods that simulate relevant contact conditions. Testing in Hanks’ solution allows the friction and wear behavior of lead insulation materials to be compared under a simulated body-fluid condition rather than relying only on dry testing.

Nano-friction test setup used to evaluate endocardial pacing lead insulation materials under low-load contact conditions.

측정 목표

This study compares the nano-friction and wear behavior of endocardial pacing lead insulation materials in Hanks’ solution. Silicone and polyether-polyurethane lead materials were evaluated to determine how each material responds under simulated body-fluid conditions.

Low-load nano-friction testing was performed using the Nano Module of the 나노베아 기계식 테스터 to measure coefficient of friction at controlled contact force. Reciprocating wear testing was then performed using a NANOVEA Tribometer to compare wear resistance under linear sliding contact.

나노비아 T50 컴팩트
자유 중량 트라이보미터

나노비아 PB1000 대형 플랫폼 기계 테스터

Measurement Principle

Nano-Friction Measurement Principle

Nano-friction testing measures the coefficient of friction (COF) between the test surface and a controlled counter material under very low applied load. In this study, the indenter made contact with the pacing lead insulation surface while the Nano Module maintained a constant load throughout the measurement.

The Nano Module uses a fast piezoelectric system and load cell to adjust the ball position and keep the applied load stable during sliding. The sample is moved at a controlled speed while lateral force is measured and plotted against displacement.

A stainless steel ball with a 6 mm diameter is commonly used for this type of measurement, although other counter materials, shapes, and sizes can be selected to simulate different contact conditions. This allows pacing lead insulation materials to be evaluated under controlled low-load friction conditions relevant to biomedical device applications.

Nano-friction measurement schematic showing controlled low-load sliding contact and lateral force measurement during reciprocating motion.

Reciprocating Wear Principle

Reciprocating wear testing evaluates material response under repeated linear sliding contact. A flat or spherical counter material is loaded against the test sample with a precisely known force, while the sample moves back and forth in a controlled reciprocating motion.

The counter material, such as a pin or ball, is mounted on a stiff lever that functions as a low-friction force transducer. As the sample moves, frictional forces between the counter material and the sample are measured using a strain gauge sensor on the tribometer arm.

After the test, the resulting wear track can be examined to compare material damage, wear scar geometry, and surface response. This method allows friction and wear behavior to be studied under controlled conditions, including variations in time, contact pressure, sliding speed, temperature, humidity, and lubrication environment.

Linear reciprocating wear schematic showing a pin or ball counterface sliding across the sample to generate a wear track under controlled load.

테스트 절차

The coefficient of friction (COF) of the pacing lead materials was measured against a stainless steel 440 ball with a 6 mm diameter. Testing was performed using the Nano Module of the Nanovea Mechanical Tester.

The sample was immersed in Hanks’ solution to simulate a body-fluid environment. A low applied load of 50 mN was maintained throughout the test, while the ball slid against the lead surface at a constant speed of 20 mm/min over a total sliding distance of 10 mm.

Wear resistance was evaluated using a Nanovea Tribometer with the Linear Reciprocating Wear Module. During the wear test, a stainless steel 303 block measuring 10 × 10 mm² was used as the counter material, and the coefficient of friction was recorded in situ at 0.1 s intervals.

After testing, the resulting wear tracks were examined under an optical microscope to compare surface damage on the silicone and polyether-polyurethane lead materials. Stainless steel was used as the counter material in this study; however, custom fixtures and alternative counter materials can be used to simulate specific application conditions.

Parameter	Value
Sample	Leads made of silicone or polyether-polyurethane (PP)
Normal force	1 N
속도	200 cycles/min
Duration of test	5 h
환경	Hanks’ solution

Wear test parameters used to evaluate silicone and polyether-polyurethane pacing lead materials in Hanks’ solution.

결과 및 토론

Nano-Friction Test

The nano-friction behavior of the silicone and polyether-polyurethane (PP) pacing lead materials was first evaluated using the Nano Module of the Nanovea Mechanical Tester. The coefficient of friction was measured in both dry conditions and Hanks’ solution to compare material response under ambient and simulated body-fluid environments.

Both materials showed significantly lower coefficient of friction in Hanks’ solution than under dry conditions. In Hanks’ solution, the silicone lead exhibited a COF of approximately 0.15, while the polyether-polyurethane lead exhibited a lower COF of approximately 0.05. Under dry conditions, the values were substantially higher, at approximately 0.6 for silicone and 0.5 for polyether-polyurethane.

These results demonstrate the importance of testing pacing lead insulation materials under application-relevant environmental conditions. Hanks’ solution had a strong effect on the measured friction behavior, showing that dry testing alone may not represent the tribological response of lead insulation materials in a simulated body-fluid environment.

The low-load control of the Nano Module allowed the applied force to remain constant at 50 mN during the measurement. This enabled controlled simulation of low-contact-force interaction between the lead material and surrounding biological structures.

Coefficient of friction comparison for silicone and polyether-polyurethane pacing lead materials in dry conditions and Hanks’ solution.

Wear Test

Wear resistance was evaluated using a Nanovea Tribometer to compare the silicone and polyether-polyurethane pacing lead materials in Hanks’ solution. After testing, the lead surfaces were examined visually and under optical microscopy to compare the extent of wear damage.

The silicone lead showed a large wear scar with a width of approximately 1.2 mm. Microscopic observation indicated severe wear on the silicone lead, with parallel deep grooves formed along the movement direction of the rubbing block.

In comparison, the polyether-polyurethane lead showed a narrower wear scar of approximately 0.6 mm. The observed wear was milder, with only several small scratches visible on the shallow surface.

Wear of the lead outer insulation can contribute to pacing and sensing abnormalities, making wear resistance an important factor in endocardial lead material selection.⁶ These results indicate that polyether-polyurethane provided lower friction and better wear resistance than silicone under the tested conditions.

Before-and-after wear comparison of silicone and polyether-polyurethane pacing lead surfaces, including 400x microscope images showing more severe wear on silicone and milder wear on polyether-polyurethane.

Silicone pacing lead surface before reciprocating wear testing.

Polyether-polyurethane pacing lead surface before reciprocating wear testing.

Silicone pacing lead surface after wear testing, showing a pronounced wear scar.

Polyether-polyurethane pacing lead surface after reciprocating wear testing.

400x microscope image of the silicone pacing lead after wear testing, showing deep parallel wear grooves.

400x microscope image of the polyether-polyurethane pacing lead after wear testing, showing comparatively mild surface wear.

결론

This study demonstrated the use of low-load nano-friction testing and reciprocating wear testing to evaluate endocardial pacing lead insulation materials in Hanks’ solution. The Nano Module of the NANOVEA Mechanical Tester measured coefficient of friction under controlled low-load contact, while the NANOVEA Tribometer simulated wear behavior under reciprocating sliding motion.

Testing in Hanks’ solution showed a clear difference between silicone and polyether-polyurethane lead materials. Polyether-polyurethane exhibited lower coefficient of friction and better wear resistance than silicone under the tested conditions, making it the stronger candidate for the outer insulation material of endocardial pacing leads in this study.

These results highlight the importance of evaluating biomedical materials under application-relevant environments rather than relying only on dry testing. Controlled nano-friction and tribology testing can help compare candidate materials, quantify friction response, and evaluate wear resistance for implantable medical device components.

The NANOVEA Mechanical Tester’s Nano, Micro, and Macro modules operate within a single ISO and ASTM compliant platform, enabling consistent evaluation of hardness, elastic modulus, fracture toughness, and wear from a single system. The NANOVEA Tribometer similarly supports rotative and linear wear modes with optional high-temperature, corrosion, and liquid environment modules.

참조

[1] Magney JE, Flynn DM, Parsons JA, Staplin DH, Chin-Purcell MV, Milstein S, Hunter DW. Pacing Clin Electrophysiol. 1993; 16:445–457.
[2] Jacobs DM, Fink AS, Miller RP, Anderson WR, McVenes RD, Lessar JF, Cobian KE, et al. Pacing Clin Electrophysiol. 1993; 16:434–444.
[3] Gupta K, Villareal RP, Rasekh A, Massumi A. Tex Heart Inst J. 2003; 30:84–85.
[4] Magney JE, Parsons JA, Flynn DM, Hunter DW. Pacing Clin Electrophysiol. 1995; 18:1509–1517.
[5] Kazama S, Nishiyama K, Machii M, Tanaka K, Amano T, Nomura T, Ohuchi M, et al. Jpn Heart J. 1993; 34:193–200.
[6] Andrzej K, Barbara M, Agnieszka K, Marcin G. Pacing Clin Electrophysiol. 2013; 36(12):1503–1511.

Frequently Asked Questions About Pacing Lead Insulation Wear Testing

How do you evaluate friction and wear behavior of pacing lead insulation?

Pacing lead insulation can be evaluated using low-load friction testing and reciprocating wear testing. These methods measure coefficient of friction, wear scar formation, and surface damage under controlled load, motion, and environmental conditions.

Why is low-load friction testing important for endocardial leads?

Endocardial leads operate under relatively low contact forces while interacting with blood vessels, tissue, and surrounding structures. Low-load friction testing helps evaluate how insulation materials behave under contact conditions that are closer to the application than high-force mechanical testing alone.

What does coefficient of friction indicate in pacing lead material testing?

Coefficient of friction indicates how much resistance occurs during sliding contact between the lead insulation and a counter material. In this study, lower COF values in Hanks’ solution showed that the test environment had a strong effect on the measured friction behavior of silicone and polyether-polyurethane materials.

Why compare silicone and polyether-polyurethane lead insulation materials?

Silicone and polyether-polyurethane are commonly considered for flexible biomedical insulation applications because they can provide different combinations of flexibility, durability, and surface response. Comparing them under the same test conditions helps identify which material provides lower friction and better wear resistance for the intended application.

Which NANOVEA instruments are used for low-load friction and wear testing?

Low-load coefficient of friction can be measured using the Nano Module of a NANOVEA Mechanical Tester, while reciprocating wear behavior can be evaluated using a NANOVEA Tribometer. Together, these systems allow controlled evaluation of friction, wear, and material response for biomedical components.

How is reciprocating wear testing used for pacing lead materials?

Reciprocating wear testing repeatedly slides a counter material across the sample surface under controlled load to create and evaluate a wear track. For pacing lead insulation materials, this allows comparison of wear scar width, surface damage, and material durability under simulated sliding contact.

Need Reliable Medical Device Friction and Wear Testing?

The post Pacing Lead Insulation Wear Testing in Hanks’ Solution appeared first on NANOVEA: Advanced Profilometers, Tribometers, Nanoindenters, and Scratch Testers for Materials Testing.

Climbing Hold Surface Roughness Analysis

Andrew Shore — Thu, 28 May 2026 20:27:37 +0000

Application Note | 3D Optical Profilometry

Climbing Hold Surface Roughness Analysis Using 3D Optical Profilometry

Measuring Texture, Porosity, and Topography on Bouldering Holds

Research & Experimental Testing

Walter Alabiso, PhD

Visual Design & Editorial

앤드류 쇼어

소개

Bouldering is a demanding discipline that combines physical strength, precise body positioning, and an understanding of how the human body interacts with climbing surfaces. On slab routes, where the wall is angled below vertical and positive holds are limited or absent, a climber’s stability depends almost entirely on the tribological interaction between the body and the climbing hold surface.

Climbing hold surface roughness plays a central role in this contact. Roughness provides the microtexture needed for smearing, a technique where high-friction rubber soles are pressed firmly against the surface to expand the effective contact area and generate adherence. A similar mechanism occurs at the fingers, where the ridges of fingerprints and the pliability of skin deform slightly against the hold’s surface features, creating grip through microscopic interlocking.

Porosity contributes to grip performance by absorbing moisture, sweat, or chalk at the contact interface, preventing the formation of a thin lubricating film that would reduce friction. Micro-cracks and surface flaws act as additional friction points, helping the climber maintain lateral tension against the hold surface. Because these features (roughness, porosity, and surface morphology) operate at different scales and interact differently depending on the hold, quantitative 3D surface measurement is essential for comparing how different climbing hold textures perform under real contact conditions.

Bouldering grips used to compare surface roughness, pore morphology, and grip-related topography.

Why Use Non-Contact Profilometry for Climbing Hold Surface Analysis

Climbing holds and rock-like surfaces can include deep pores, steep asperities, sharp valleys, and irregular texture. These features are difficult to measure accurately with contact-based profilometry because a physical stylus can lose contact, deform local surface features, or fail to reach narrow cavities.

NANOVEA’s non-contact optical profilometry uses chromatic light technology to capture surface height data without touching the sample. This makes it suitable for reconstructing complex climbing hold topography, including deep nooks, pores, and surface flaws, while avoiding measurement artifacts caused by local plastic deformation.

In this study, the NANOVEA JR25 Optical Profiler was used to measure two bouldering grips: a yellow block with a smoother, flatter surface and a green block with a rougher tactile texture. Both samples were scanned using a PS4-MG35 single-point optical sensor with a 3000 µm Z-range and a 4 µm acquisition step in X and Y.

Dual-frequency acquisition was used to reduce light sensor saturation from localized bright spots on the grip surfaces, allowing the profiler to capture roughness and pore morphology across the scanned areas.

측정 목표

The objective of this study was to demonstrate how non-contact 3D optical profilometry can be used to reconstruct and compare the surface roughness, topography, and pore morphology of climbing holds.

Two bouldering grip samples were analyzed: a yellow hold with a smoother, flatter surface and a blue hold with a rougher tactile texture and sharper grip features. The analysis focused on surface height variation, areal roughness parameters, pore coverage, pore size, pore depth, and functional surface behavior.

The NANOVEA JR25 Optical Profilometer measuring the climbing hold samples using an optical sensor.

Measurement Method

The NANOVEA JR25 Optical Profiler was used to measure the yellow and blue bouldering grip samples. Each surface was scanned with a PS4-MG35 single-point optical sensor with an enhanced 3000 µm Z-range, allowing the system to capture deep pores, sharp valleys, and irregular surface texture while maintaining a 4 µm acquisition step in X and Y.

Dual-frequency acquisition was used to reduce light sensor saturation from localized bright spots on the grip surfaces, improving data capture across rough, porous, and uneven areas.

나노비아 JR25 Portable

광학 프로파일로미터

테스트 매개변수

Measurement Setting	Optical Profilometry Setup
Samples measured	Yellow and blue bouldering grip samples
Optical pen	PS4-MG35
Z-range	3000 µm
Scan area	5.00 mm × 5.00 mm
X-step size	4.00 µm
Y-step size	4.00 µm
Averaging	1
Measurement type	Direct
Acquisition mode	Dual frequency
Acquisition rate	100–400 Hz
Light intensity	100%

Optical profilometry test conditions used to measure the bouldering grip samples.

Optical Profilometry Results

Yellow Grip Sample

Surface Roughness Analysis

The 3D rendering below shows the reconstructed surface topography of the yellow climbing grip sample.

A total least-squares plane was removed to study surface properties. The roughness filters S-Gaussian 2.5 µm was applied following ISO 25178 (1/2 cut-off removed at each side). However, the sharp density of pores and asperities and the elevated average roughness make the use of a Gaussian L-filter (8 mm cut off) inapplicable. Therefore, the primary surface was considered, and the roughness parameters are listed in the table below, alongside the 2D false-color map of the filtered surface.

ISO 25178-2 – Primary Surface
S-filter (λs): Gaussian, 2.5 µm, 1/2 cut-off
F-operation: [Workflow] Leveled (TLSPL)
Height Parameters
Sq	168.970	µm	제곱 평균 제곱근 높이
Ssk	-0.927		기울기
SKU	4.117		첨도
Sp	320.530	µm	최대 피크 높이
Sv	868.116	µm	Maximum pit depth
Sz	1188.645	µm	최대 높이
Sa	132.953	µm	산술 평균 높이

The average surface roughness Sa is 132.953 µm, whereas the peak-to-valley roughness, Sz amounts to 1188.645 µm. The surface morphology is skewed towards deep valleys (Ssk < 0, Sv > Sp), with a leptokurtotic (SKU > 3) distribution of peaks and valleys relative to the average plane.

The following picture shows a 2D photo-simulation of the area under artificial lighting, highlighting the region’s morphology.

Pore Morphology Analysis

A pore analysis was performed across the full scanned area using a semi-automated edge-detection algorithm. The analysis identified recessed surface features to quantify pore coverage, pore density, radius, void volume, and maximum depth.

The detected pore locations were then mapped across the scanned 5 mm × 5 mm area to evaluate pore coverage, density, and size distribution.

Information
Method	Circle detection
Features detected	Pores, recessed objects
Minimum detection diameter	0.150 mm
Maximum detection diameter	2.000 mm
Number of detected pores	206
Surface coverage	47.395%
Pore density	8.203 particles/mm²

Parameter	Unit	Mean	Std. Dev.	Min	Max
Global Statistics
반경	mm	0.127	0.049	0.076	0.275
Void volume	µm³	4,724,770.705	6,748,143.925	23,594.172	4.422 × 10⁷
Maximum depth	µm	173.729	94.942	28.153	716.480

Pores covered nearly half of the yellow grip’s scanned surface, with a measured coverage of 47.395% and a pore density of 8.203 particles/mm². The detected pores and cracks were highly heterogeneous in size, volume, and depth, ranging from large crater-like features with a maximum radius of 0.275 mm and void volume above 4.4 × 10⁷ µm³ to smaller pores with a minimum radius of 0.076 mm and void volume of 23,594.172 µm³. This uneven pore distribution is reflected in the large standard deviation measured for void volume and maximum depth.

Functional Surface Parameters (Abbott-Firestone curve)

The Abbott-Firestone curve shows the cumulative areal material distribution of the yellow climbing grip sample. This analysis defines functional surface parameters including Sk, Spk, and Svk according to ISO 25178-2.

Information
표준	ISO 25178-2
Parameter	Value	Unit
Sk	409.738	µm
Spk	45.480	µm
Svk	233.446	µm
Smrk1	3.976	%
Smrk2	85.005	%

The chart below shows the peak-valley distribution from the mean plane based on the functional parameters derived from the Abbott-Firestone curve. Valleys are shown in purple, the mean plane in green, and peaks in orange.

Information
1st threshold	Height – c1: 229.209 µm
2nd threshold	Height – c2: -180.424 µm
Parameters	Unit
Projected area (in %)	%	14.995	81.029	3.976
Projected area	mm²	3.772	20.381	1.000
Volume of material (in %)	%	97.451	48.100	0.973
Volume of material	µm³	1.684 × 10¹⁰	4.956 × 10⁹	2.275 × 10⁷

The yellow grip sample shows a dominant mean-plane region with scattered recessed pores and a smaller population of raised peaks. This indicates a surface texture characterized mainly by average-sized pores distributed across the scanned area.

Blue Grip Sample

Surface Roughness Analysis

The 3D rendering below shows the reconstructed surface topography of the blue climbing grip sample.

A total least-squares plane was removed to evaluate the blue grip’s surface properties. An S-Gaussian 2.5 µm roughness filter was applied following ISO 25178, with 1/2 cut-off removed at each side.

Because of the dense pores, asperities, and elevated average roughness, a Gaussian L-filter with an 8 mm cut-off was not applied. The primary surface was used for roughness analysis, with the roughness parameters listed alongside the 2D false-color map of the filtered surface.

ISO 25178-2 – Primary Surface
S-filter (λs): Gaussian, 2.5 µm, 1/2 cut-off
F-operation: [Workflow] Leveled (TLSPL)
Height Parameters
Sq	211.440	µm	제곱 평균 제곱근 높이
Ssk	-0.682		기울기
SKU	3.672		첨도
Sp	522.404	µm	최대 피크 높이
Sv	720.164	µm	Maximum pit depth
Sz	1242.568	µm	최대 높이
Sa	166.719	µm	산술 평균 높이

The blue grip sample had an average surface roughness, Sa, of 166.719 µm and a peak-to-valley roughness, Sz, of 1242.568 µm. The negative skewness value, Ssk < 0, indicates that the surface morphology is skewed toward deep valleys, while Sv > Sp shows that the maximum pit depth exceeded the maximum peak height.

The kurtosis value, Sku > 3, indicates a leptokurtotic height distribution, meaning the blue grip surface contains sharper or more extreme peaks and valleys relative to the average plane.

The 2D photo simulation below highlights the blue climbing grip’s surface morphology under artificial lighting.

Pore Morphology Analysis

The detected pore locations were mapped across the scanned 5 mm × 5 mm area to evaluate pore coverage, density, and size distribution.

Information
Method	Circle detection
Features detected	Pores, recessed objects
Minimum detection diameter	0.040 mm
Maximum detection diameter	2.000 mm
Number of detected pores	794
Surface coverage	24.208%
Pore density	31.355 particles/mm²

Parameter	Unit	Mean	Std. Dev.	Min	Max
Global Statistics
반경	mm	0.035	0.035	0.020	0.218
Void volume	µm³	821,872.849	2,495,310.021	11,009.819	2.929 × 10⁷
Maximum depth	µm	476.053	305.830	16.132	1044.045

Pores covered 24.208% of the blue grip’s scanned surface, with a pore density of 31.355 particles/mm². The detected pores and cracks were highly heterogeneous in size, volume, and depth, ranging from large crater-like features with a maximum radius of 0.218 mm and void volume greater than 2.9 × 10⁷ µm³ to small pores with a minimum radius of 0.020 mm and void volume of approximately 1.1 × 10⁴ µm³.

This uneven distribution is reflected in the large standard deviation measured for void volume and maximum depth. The pore distribution is bimodal, with one population of fine, deep pores and another population of larger crater-like valleys.

Functional Surface Parameters (Abbott-Firestone curve)

The Abbott-Firestone curve shows the cumulative areal material distribution of the blue climbing grip sample. This analysis defines functional surface parameters including Sk, Spk, and Svk according to ISO 25178-2.

Information
표준	ISO 25178-2
Parameter	Value	Unit
Sk	522.359	µm
Spk	117.670	µm
Svk	295.209	µm
Smrk1	6.122	%
Smrk2	87.456	%

Information
1st threshold	Height – c1: 283.646 µm
2nd threshold	Height – c2: -238.619 µm
Parameters	Unit
Projected area (in %)	%	12.544	81.334	6.122
Projected area	mm²	3.182	20.629	1.553
Volume of material (in %)	%	96.079	48.546	1.514
Volume of material	µm³	1.151 × 10¹⁰	6.431 × 10⁹	9.142 × 10⁷

The blue grip sample shows a dominant mean-plane region with fine, deep pores distributed across the surface and localized peak features. Compared with the yellow grip, the blue grip contains a higher projected peak area and a bimodal pore structure, combining fine recessed pores with larger crater-like valleys.

결론

In this application, the NANOVEA JR25 Non-Contact Optical Profiler was used to measure the surface roughness, topography, and pore morphology of yellow and blue bouldering grip samples.

Topographic analysis showed that both grip samples had high surface roughness, with Sa values above 100 µm and Sz values above 1000 µm. Both surfaces also showed an asymmetric height distribution skewed toward valleys, indicating that recessed features played a major role in the measured surface morphology.

The yellow grip sample showed higher pore coverage, with pores covering 47.395% of the scanned surface. Its surface was mainly characterized by average-sized pores distributed across the measured area.

The blue grip sample showed lower pore coverage at 24.208%, but a much higher pore density of 31.355 particles/mm². Its pore distribution was bimodal, with a population of fine, deep pores and a separate population of larger crater-like valleys.

These results show how non-contact 3D optical profilometry can quantify climbing hold surface features that are difficult to evaluate from visual inspection alone, including roughness, pore coverage, pore depth, surface height distribution, and functional topography. The blue grip’s higher porosity and bimodal pore structure make it more likely to absorb moisture and chalk at the contact interface, while its elevated roughness and surface morphology support stable friction for shoe rubber and finger contact. The yellow grip’s lower roughness and flatter profile suggest it is better suited for use as a foothold in slab climbing, where broad surface contact matters more than deep textural engagement.

Frequently Asked Questions About Climbing Hold Surface Roughness

What is climbing hold surface roughness?

Climbing hold surface roughness describes the height variation, texture, pores, asperities, and valleys present on the surface of a climbing grip. These features can influence contact behavior between the hold, shoe rubber, skin, chalk, and moisture.

How can climbing hold surface roughness be measured?

Climbing hold surface roughness can be measured using non-contact 3D optical profilometry. This method reconstructs the surface topography and calculates areal roughness parameters such as Sa, Sz, Sp, Sv, Ssk, and Sku without touching or deforming the sample.

Why use non-contact optical profilometry for climbing hold analysis?

Non-contact optical profilometry is useful for climbing hold analysis because climbing grips can contain deep pores, sharp valleys, rough asperities, and irregular surface texture. A contact stylus may lose contact, fail to reach recessed features, or introduce artifacts on complex surfaces.

What does Sa mean in surface roughness analysis?

Sa is the arithmetic mean height of a surface and is commonly used to describe average areal surface roughness. In this app note, both climbing grip samples showed high Sa values above 100 µm, indicating strongly textured surfaces.

What does Sz mean in optical profilometry results?

Sz is the maximum height of the measured surface, calculated from the highest peak to the deepest valley. In climbing hold surface roughness analysis, Sz helps describe the full vertical range of the grip’s surface texture.

Why is pore morphology important for climbing grips?

Pore morphology can affect how a climbing grip interacts with chalk, sweat, humidity, skin, and shoe rubber. Measuring pore coverage, density, depth, and volume helps quantify surface features that are difficult to evaluate by visual inspection alone.

Need Reliable Surface Roughness Analysis?

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Stent Coating Adhesion and Delamination Analysis Using Nano Scratch Testing

Andrew Shore — Wed, 25 Mar 2026 20:57:16 +0000

Application Note | Stent Coating Adhesion Testing

Stent Coating Adhesion and Delamination Analysis Using Nano Scratch Testing

Quantifying Coating Failure and Adhesion Performance on Drug-Eluting Stents

Research & Experimental Testing

Duanjie Li, PhD

Visual Design & Editorial

앤드류 쇼어

소개

Blood is carried through arteries from the heart to the rest of the body. Any weakening or blockage of these vessels can pose significant health risks and may become life-threatening. A stent is a small mesh tube inserted into the lumen of a blood vessel to treat narrowed or weakened arteries. Stent implantation is now a widely used procedure to support the arterial wall and restore blood flowᶦ.

Metal stent mesh geometry illustrating the structural complexity of vascular implant design.

Why coating adhesion matters in drug-eluting stents

Drug-eluting stents represent a major advancement in stent technology. They incorporate a biodegradable, biocompatible polymer coating that enables controlled drug release at the arterial site, helping to inhibit intimal thickening and reduce the risk of restenosisᶦᶦ.

A critical concern in these systems is the delamination of the polymer coating from the metallic stent substrate. This coating carries the drug-eluting layer, and its adhesion directly impacts device performance and reliability.

To improve coating adhesion, stents are often designed with complex geometries. In this study, the polymer coating is located at the bottom of grooves within the stent mesh. This configuration presents a significant challenge for adhesion measurement.

A reliable method is required to quantitatively evaluate the interfacial strength between the polymer coating and the metal substrate. The small diameter of the stent mesh, comparable to a human hair, combined with its three-dimensional geometry, requires:

ultrafine X-Y positioning accuracy
precise control of applied load
accurate depth measurement during testing

ℹ️ 자세히 알아보기 nanoindentation and scratch testing lab services for coating adhesion and failure analysis.

Measurement Method

Nano scratch testing is performed using the 나노베아 PB1000 기계식 테스터, in Nano Scratch Mode, to evaluate the cohesive and adhesive strength of the polymer coating on the metal mesh of stent samples.

Controlled scratch measurements are carried out on stent geometries with dimensions comparable to a human hair, enabling precise evaluation of coating adhesion on complex stent structures.

나노비아 PB1000 Advanced

기계 테스터

테스트 조건

1. Regular Stent Samples

The stent is fixed on the sample stage, with a support wire inserted inside the stent tube to ensure stability during nano scratch testing. The NANOVEA Mechanical Tester is used to perform nano scratch measurements using the parameters summarized in Table 1, to evaluate the cohesive and adhesive strength of the polymer coating on the metal substrate.

Parameter	Value
Load type	프로그레시브
Initial load	0.05 mN
Final load	300 and 100 mN
Sliding speed	0.5 mm/min
Sliding distance	0.5 mm
Indenter geometry	원뿔형
Indenter material (tip)	다이아몬드
들여쓰기 팁 반경	20 µm
온도	24°C (room)

표 1: Test parameters for nano scratch measurements on regular stent samples

2. Grooved Stent Samples

The SEM image in Fig. 1 shows the cross-section of the stent sample. The stent features a groove with a depth of approximately 30 µm. The polymer coating, with a thickness of 10.8 µm, is located at the bottom of the groove.

Standard 60° conical diamond tips are not sharp enough to reach the bottom of the groove without contacting the sidewalls. Therefore, a sharper 40° conical diamond tip is used in this study (Fig. 2).

Nano scratch measurements are performed using the parameters summarized in Table 2.

Parameter	Value
Load type	프로그레시브
Initial load	0.1 mN
Final load	300 mN
로딩 속도	300 mN/min
Scratch length	0.25 mm
Scratch speed	0.25 mm/min
Indenter geometry	40° cone
Indenter material (tip)	다이아몬드
들여쓰기 팁 반경	5 µm

Table 2: Test parameters for nano scratch measurements on grooved stent samples

Fig. 1: SEM cross-section of a grooved stent showing polymer coating located at the bottom of the groove, highlighting the challenge of coating adhesion measurement in recessed geometries.

Fig. 2: Schematic of a 40° conical diamond tip designed for nano scratch testing inside stent grooves, enabling accurate adhesion measurement without sidewall interference.

결과 및 토론

The stent mesh has a diameter of approximately 100 μm, comparable to a human hair. Precise positioning is therefore critical to ensure the scratch test is performed at the center of the stent mesh. The NANOVEA Mechanical Tester provides X–Y positioning accuracy down to 0.25 μm, enabling accurate test placement under the integrated optical microscope.

1. Regular Stent Samples

Nano scratch testing is performed with a progressively increasing load up to 300 mN. The full scratch track on the stent is shown in Fig. 3a, while failure behavior at different stages is presented in Fig. 3b and 3c.

Two critical loads are identified:

Lc1: the load at which the first visible damage appears on the coating
Lc2: the load at which the coating is fully removed and the substrate is exposed

The evolution of coefficient of friction (COF) and penetration depth is shown in Fig. 4, providing insight into the progression of coating failure during the test.

The first signs of coating damage appear at Lc1 ≈ 14.5 mN. As the applied load increases, the diamond tip progressively penetrates the polymer coating, resulting in a wider and deeper scratch track. During this phase, the COF increases from approximately 0.05 to 0.7.

At Lc2 ≈ 78.1 mN, the coating is fully delaminated from the metal substrate. Beyond this point, as the load continues to increase, both COF and penetration depth remain relatively stable due to the mechanical support of the underlying metal substrate.

(a) Full Scratch Track

(b) Lc1 ≈ 14.5 mN

Fig. 3: Nano scratch track on a stent coating under progressively increasing load, showing (a) full scratch path, (b) initial coating failure at Lc1 ≈ 14.5 mN, and (c) complete coating delamination at Lc2 ≈ 78.1 mN.

Fig. 4: Evolution of coefficient of friction (COF) and penetration depth during nano scratch testing of a stent coating under progressively increasing load, showing the progression of coating failure and transition to substrate support.

Failures during nano scratch testing up to a maximum load of 300 mN occur at critical loads below 100 mN. To enable a more quantitative comparison of coating performance, additional tests are performed with a maximum load of 100 mN on two stent samples, referred to as Sample 1 and Sample 2.

Fig. 5 compares the scratch tracks of Sample 1 and Sample 2 after nano scratch testing. Sample 1 exhibits the first sign of coating damage at a critical load of Lc1 ≈ 13.2 mN, while Sample 2 shows initial failure at a higher load of Lc1 ≈ 21.1 mN.

Coating delamination occurs at 62.5 mN for Sample 1. In contrast, the coating on Sample 2 remains intact throughout the test, continuing to protect the metal substrate under the same loading conditions.

This behavior is further reflected in the evolution of coefficient of friction (COF) and penetration depth, as shown in Fig. 6. When the diamond tip penetrates through the coating and contacts the metal substrate in Sample 1, the COF reaches a peak while the penetration depth decreases due to the increased stiffness of the underlying substrate.

(a) Sample 1 – Early Coating Failure

(b) Sample 2 – Improved Coating Integrity

Fig. 5: Comparison of nano scratch tracks for two stent coatings, showing (a) early coating failure and delamination in Sample 1, and (b) improved coating integrity in Sample 2 under the same loading conditions.

Fig. 6: Comparison of coefficient of friction (COF) and penetration depth for Sample 1 and Sample 2 during nano scratch testing, showing earlier substrate contact and higher friction response in Sample 1, indicating weaker coating adhesion.

2. Grooved Stent Samples

As shown in Fig. 1 and Fig. 7, the grooved stent mesh has a diameter of approximately 90 μm, comparable to a human hair. The groove has a width of ~50 μm and a depth of 30 μm. This geometry presents a significant challenge for nano scratch testing, particularly for evaluating coating adhesion at the bottom of the groove.

Precise positioning is critical to locate the scratch test within the groove. The nano scratch test is performed with a progressively increasing load up to 300 mN. The full scratch tracks of grooved stent Samples 3 and 4 are compared in Fig. 7.

The critical load Lc is defined as the load at which the coating fails and the substrate becomes exposed. The evolution of normal load and penetration depth, shown in Fig. 8, provides further insight into the progression of coating failure during testing.

As the applied load increases, the diamond tip progressively penetrates the polymer coating, resulting in a deeper scratch track. When the critical load Lc is reached, the coating delaminates from the metal substrate.

Sample 3 exhibits coating failure at Lc ≈ 126 mN, while Sample 4 fails at a higher load of Lc ≈ 173 mN. This difference indicates stronger adhesion of the coating in Sample 4.

The measured critical loads enable quantitative comparison of coating adhesion performance. Under the same testing conditions, the coating on Sample 4 demonstrates higher resistance to delamination, making it the better-performing candidate in this study.

(d) Sample 4 – Higher Adhesion in Groove (Lc ≈ 173 mN)

Fig. 7: Nano scratch tracks inside stent grooves for Samples 3 and 4, showing (c) coating failure at Lc ≈ 126 mN in Sample 3 and (d) higher adhesion with delayed failure at Lc ≈ 173 mN in Sample 4.

(a) Sample 3 – Earlier Coating Failure (Lc ≈ 126 mN)

(b) Sample 4 – Delayed Failure and Higher Adhesion (Lc ≈ 173 mN)

Fig. 8: Evolution of normal load and penetration depth during nano scratch testing inside stent grooves for Samples 3 and 4, showing earlier coating failure in Sample 3 and delayed failure at higher load in Sample 4. The vertical green line indicates the critical load (Lc) where coating delamination occurs.

결론

This study demonstrates the ability of the NANOVEA Mechanical Tester to quantitatively evaluate the cohesive and adhesive strength of polymer coatings on both regular and grooved stent geometries using nano scratch testing.

The recessed geometry of the stent grooves, approximately 50 μm wide and 30 μm deep, presents a significant challenge for coating adhesion measurement. The high X–Y positioning accuracy of 0.25 μm enables precise placement of the scratch test within these confined regions, allowing direct evaluation of coating performance where failure is most critical.

By applying a controlled, progressively increasing load, critical loads associated with coating failure can be identified and compared across samples. This approach enables reliable differentiation of coating adhesion performance and interfacial integrity, even on small, complex stent structures.

참조

[I] http://www.nhlbi.nih.gov/health/health-topics/topics/stents
[II] http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1405-99402006000300008

Frequently Asked Questions About Stent Coating Adhesion Testing

What is stent coating adhesion testing?

Stent coating adhesion testing evaluates how strongly a polymer coating is bonded to the metal substrate of a stent. Techniques such as nano scratch testing quantify the load at which coating damage and delamination occur, providing measurable indicators of adhesion strength.

What is critical load (Lc) in nano scratch testing?

Critical load (Lc) is the applied load at which a coating fails during a scratch test.

Lc1 corresponds to the first visible damage in the coating
Lc2 indicates complete coating removal and exposure of the substrate

These values are used to quantify and compare coating adhesion performance.

Why is coating adhesion important in drug-eluting stents?

Coating adhesion directly affects the reliability of drug-eluting stents. Poor adhesion can lead to coating delamination, which may compromise controlled drug release and increase the risk of device failure.

How do you measure coating adhesion inside stent grooves?

Measuring adhesion inside stent grooves requires high positioning accuracy and appropriate indenter geometry. Nano scratch testing with sharp diamond tips allows access to recessed coating regions, enabling direct evaluation of adhesion within complex stent geometries.

What does coefficient of friction (COF) indicate in scratch testing?

The coefficient of friction (COF) reflects changes in surface interaction during the scratch test. A sudden increase in COF often indicates coating failure and contact between the indenter and the underlying metal substrate.

How can nano scratch testing compare different coating formulations?

Nano scratch testing enables direct comparison of coatings by measuring critical loads under controlled conditions. Higher critical loads indicate stronger adhesion and improved resistance to delamination, allowing selection of better-performing coating systems.

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Dental Surface Roughness Measurement & 3D Tooth Topography

Andrew Shore — Thu, 05 Mar 2026 21:02:01 +0000

Application Note | Dental Surface Characterization

Dental Surface Roughness Measurement and Full 3D Tooth Topography

Surface Roughness Analysis Using Non-Contact Optical Profilometry

작성자

Walter Alabiso, PhD; Davide Morrone, MPhys; Andrew Shore, MA

소개

The ability to accurately characterize tooth surfaces, including micro-roughness and 3D surface topography at the nanometer scale, enables advanced research and applications in orthodontics and dental materials science. Non-contact optical profilometry provides a precise method for measuring dental surface roughness and analyzing tooth surface morphology without damaging delicate structures. These measurements support the development of composite dental materials that replicate the natural surface roughness of enamel, as well as the design and fabrication of patient-specific dental casts and restorative components.

Low surface roughness plays a primary role in limiting bacterial adhesion and plaque formation, thereby reducing the risk of cavities. An increase in average roughness (Ra) above 2 µm leads to a steep increase in biofilm formation in vivo.¹ An Ra of 0.2 µm is considered the threshold value below which no further reduction in bacterial adhesion can be expected.²

Reconstruction of the tooth’s 3D surface topography enables the fabrication of dental casts, which are essential for accurate diagnosis, treatment planning, and the fabrication of dental appliances.

Non-Contact Optical Profilometry for Dental Surface Analysis

The present study illustrates the potential of NANOVEA’s high-precision non-contact optical profilometers for dental surface roughness measurement and 3D tooth topography analysis. Chromatic Light technology offers significant advantages over classical touch probe techniques. It acquires data points from deep crevices and complex geometries without introducing measurement errors or artifacts caused by local plastic deformation and without requiring extensive data manipulation.

Compared to focus variation systems, single-point optical sensing provides superior lateral and height accuracy, with X/Y resolution below 0.5 µm, maximum vertical resolution of 1.9 nm, and the ability to measure surface angles up to 87°. The technique is effective on transparent, opaque, specular, diffusive, polished, and rough dental surfaces, making it well suited for comprehensive dental surface characterization.

ℹ️ 자세히 알아보기 non-contact optical profilometry and surface roughness measurement services.

Measurement Method

이 애플리케이션에서는 NANOVEA JR25 Non-Contact Optical Profiler was used to analyze the surface roughness and 3D surface topography of an adult human molar previously affected by tooth decay. The side of the tooth was scanned using a PS2–MG140 single-point optical sensor to measure surface roughness parameters over a defined region of interest and along multiple line profiles.

The crown of the tooth was then scanned and reconstructed using a PS5–MG35 single-point optical sensor, which is suited for larger-area acquisition and full 3D tooth topography measurement.

나노비아 JR25 Portable
광학 프로파일로미터

Surface Measurement Using NANOVEA Optical Profilometer

Surface roughness measurements were performed on the lateral side of the molar crown, followed by full 3D reconstruction of the crown surface. Separate single-point optical sensors were used to optimize measurement accuracy for both localized roughness analysis and large-area surface topography acquisition.

PS2 – MG140

Surface roughness analysis by area and parallel line profiles on the side of the tooth’s crown.

PS5 – MG35

Full 3D surface reconstruction of the tooth’s crown.

측정 매개변수

The following measurement parameters were used for localized surface roughness analysis and full 3D surface reconstruction of the molar crown using NANOVEA single-point optical sensors.

Parameter	Roughness Analysis (Area)	Roughness Analysis (Profiles)	Full 3D Reconstruction
Optical Pen	PS2-MG140	PS2-MG140	PS5-MG35
Z-Range [µm]	300	300	10000
X-Distance [mm]	2.00	3.00	7.50
X-Step Size [µm]	1.70	1.70	10.00
Y-Distance [mm]	2.00	1.00	7.00
Y-Step Size [µm]	1.70	100.00	10.00
Averaging (Avg)	1	1	1
Measurement Type	Direct	Direct	Direct
Acquisition Mode	Single Frequency	Single Frequency	Dual Frequency
Acquisition Rate [Hz]	200	200	100–400
Light Intensity [%]	100	100	100

Optical Profilometry Results

Yellow Grip Sample

Surface Roughness Analysis

The image below shows a full 3D rendering of the yellow block’s surface.

A least-squares degree-8 polynomial form removal was applied to isolate the surface roughness component. The roughness filters S-Gaussian 2.5 µm and L-Gaussian 0.8 mm were then applied according to ISO 25178. The resulting filtered surface and corresponding roughness parameters are presented below.

ISO 25178 – Roughness (S-L)
S-filter (λs): Gaussian, 2.5 µm
F: [Workflow] Form removed (LS-poly 8)
L-filter (λc): Gaussian, 0.8 mm
Height Parameters
Sq	2.433	µm	제곱 평균 제곱근 높이
Ssk	-0.102		기울기
SKU	3.715		첨도
Sp	18.861	µm	최대 피크 높이
Sv	16.553	µm	Maximum pit depth
Sz	35.414	µm	최대 높이
Sa	1.888	µm	산술 평균 높이

The average surface roughness Sa is 1.888 µm, while the peak-to-valley height Sz reaches 35.414 µm.

A 3D surface rendering of the filtered area is shown below for visualization.

Roughness Analysis (Profiles)

Surface roughness profiles were measured using a series of 11 parallel line scans along the X direction on the side of the tooth. The false-color 2D surface map of the raw scan is shown below.

The surface form was removed using a least-squares 8-degree polynomial prior to applying the metrological filters, leaving the residual surface shown below.

A statistical analysis of the measured surface roughness profiles reveals the following line roughness parameters.

		Description	Mean	Std dev	Min	Max
ISO 4287 – Roughness (S-L)
F: 없음
S-filter (λs): Gaussian, 2.5 µm
L-filter (λc): Gaussian, 0.8 mm
Evaluation length: All λc (3)
Amplitude Parameters – Roughness Profile
Rp	µm	Maximum peak height of the roughness profile	5.683	0.761	4.315	6.610
Rv	µm	Maximum valley depth of the roughness profile	6.242	1.009	4.701	8.438
Rz	µm	Maximum height of roughness profile	11.925	1.676	9.123	15.048
Ra	µm	Arithmetic mean deviation of the roughness profile	2.063	0.297	1.710	2.629
Rq	µm	Root-mean-square (RMS) deviation of the roughness profile	2.523	0.361	2.057	3.175

F: 없음

S-filter (λs): Gaussian, 2.5 µm

L-filter (λc): Gaussian, 0.8 mm

Evaluation length: All λc (3)

The value of Ra is consistent with the Sa value extracted from the surface area measurement.

Different metrological filters can be applied to distinguish between macroscopic waviness and microscopic surface roughness. For example, a coarser filter cut-off, such as the 8 mm cut-off used with the Robust Gaussian order-2 filter, produces a smoother waviness profile (red) that is less sensitive to sharp local variations and follows the original surface profile more loosely.

Alternatively, a finer cut-off (e.g., 0.08 mm) enables the analysis of micro-roughness by removing the waviness component that follows the original profile at a larger scale, leaving the finer surface roughness features of the tooth visible.

The microroughness analysis obtained using a 0.08 mm L-Gaussian filter is presented below.

		Description	Mean	Std dev	Min	Max
ISO 4287 – Roughness (S-L)
F: 없음
S-filter (λs): Gaussian, 2.5 µm
L-filter (λc): Gaussian, 0.08 mm
Evaluation length: All λc (37)
Amplitude Parameters – Roughness Profile
Rp	µm	Maximum peak height of the roughness profile	1.582	0.122	1.342	1.748
Rv	µm	Maximum valley depth of the roughness profile	1.466	0.119	1.254	1.661
Rz	µm	Maximum height of roughness profile	3.049	0.196	2.820	3.409
Ra	µm	Arithmetic mean deviation of the roughness profile	0.495	0.047	0.423	0.597
Rq	µm	Root-mean-square (RMS) deviation of the roughness profile	0.643	0.056	0.562	0.762

F: 없음

S-filter (λs): Gaussian, 2.5 µm

L-filter (λc): Gaussian, 0.8 mm

Evaluation length: All λc (3)

Full 3D Tooth Surface Topography Reconstruction

The extended Z-scan range of the PS5 optical sensor enables high-fidelity scanning of the entire tooth crown surface. The resulting 3D surface topography is shown below.

2D VIEW: 2D surface map of the tooth crown measured with optical profilometry

3D VIEW: High-fidelity 3D rendering of the molar crown surface obtained with optical profilometry

결론

In this application, the NANOVEA JR25 Non-Contact Optical Profiler was used to measure the surface roughness and 3D surface topography of an adult human molar.

Both the area scan and the line profile analysis revealed a roughness Rq of approximately 2.5 µm and an Ra of about 1.9–2.0 µm. These values are consistent with results reported in the literature.³ The use of a narrower L-Gaussian filter with an 80 µm cut-off enabled further investigation of micro-roughness, revealing an Rq of 0.643 µm and an Ra of 0.495 µm.

The full 3D surface topography of the molar crown was reconstructed with high fidelity. The high measurement resolution allows detection of fine surface features and crevices. The resulting surface data can be easily processed and exported as STL files, enabling the design and fabrication of customized dental devices and restorative components.

참조

[1] Shin, B.W., et al. Surface Roughness of Prefabricated Pediatric Zirconia Crowns Following Simulated Toothbrushing. Pediatric Dentistry 44.5 (2022): 363–367.
[2] Bollen, C.M.L., Paul Lambrechts, and Marc Quirynen. Comparison of surface roughness of oral hard materials to the threshold surface roughness for bacterial plaque retention: A review of the literature. Dental Materials 13.4 (1997): 258–269.
[3] Suputtamongkol, K., et al. Surface roughness resulting from wear of lithia-disilicate-based posterior crowns. Wear 269.3–4 (2010): 317–322.

Frequently Asked Questions About Dental Surface Roughness Measurement

What is dental surface roughness measurement?

Dental surface roughness measurement quantifies the microscopic texture of tooth surfaces using parameters such as Ra, Rq, and Sa. Optical profilometers measure these features without contacting the surface, allowing accurate analysis of enamel, restorative materials, and dental crowns.

Why use optical profilometry to measure tooth roughness?

Optical profilometry provides non-contact surface measurement with nanometer-scale vertical resolution. It captures 2D surface maps and full 3D surface topography of dental structures without damaging soft or polished surfaces.

What roughness parameters are used for dental surface analysis?

Common roughness parameters include Ra (arithmetic mean roughness), Rq (root mean square roughness), Sa (areal roughness), and Sz (maximum surface height). These parameters help evaluate enamel wear, plaque adhesion risk, and the performance of restorative materials.

Why is surface roughness important in dentistry?

Surface roughness affects plaque retention, wear resistance, and the long-term performance of dental restorations. Controlling micro-roughness can reduce bacterial adhesion and improve the durability of dental materials.

Need Reliable Surface Roughness Measurement for Dental Materials?

The post Dental Surface Roughness Measurement & 3D Tooth Topography appeared first on NANOVEA: Advanced Profilometers, Tribometers, Nanoindenters, and Scratch Testers for Materials Testing.

휴대폰 화면 보호기의 스크래치 내성 테스트

Andrew Shore — Wed, 12 Nov 2025 17:42:04 +0000

휴대폰 화면 보호기의 스크래치 내성 테스트

작성자

스테이시 페레이라, 조슬린 에스파르자, 피에르 르루

휴대폰 화면 보호기의 스크래치 방지 기능 이해하기

휴대폰 화면의 보호 코팅은 긁힘 방지, 접착 강도 및 장기적인 내구성에 중요한 역할을 합니다. 시간이 지남에 따라 스크래치, 미세 균열 및 코팅 박리는 특히 사용 빈도가 높은 환경에서 광학 선명도와 신뢰성을 떨어뜨릴 수 있습니다. 다양한 화면 보호기가 기계적 손상에 어떻게 저항하는지 평가하기 위해 계측 스크래치 테스트를 통해 접착력, 응집력 및 파손 거동을 포함한 코팅 고장 메커니즘에 대한 정량적인 통찰력을 얻을 수 있습니다.

이 연구에서는, 나노베아 PB1000 기계식 테스터 는 제어된 점진적 하중 하에서 TPU와 강화유리 화면 보호기를 비교하는 데 사용됩니다. 정밀한 음향 방출 감지를 사용하여 임계 고장 하중을 식별하고 각 소재가 증가하는 기계적 스트레스에 어떻게 반응하는지 특성화합니다.

화면 보호기에 스크래치 내성 테스트가 중요한 이유

많은 사용자가 더 두껍거나 단단한 프로텍터가 자동으로 더 나은 성능을 발휘한다고 생각하지만 실제 내구성은 점진적인 하중, 표면 변형 및 국소 응력 하에서 재료가 어떻게 작동하는지에 따라 달라집니다. 엔지니어는 계측식 스크래치 테스트를 통해 코팅 접착력, 응집 강도, 표면 내마모성, 고장이 시작되거나 전파되는 정확한 하중을 측정할 수 있습니다.

제조업체는 균열 시작 지점, 박리 현상 및 고장 모드를 분석하여 R&D, 품질 관리 또는 비교 벤치마킹을 위해 화면 보호기 성능을 검증할 수 있습니다. 나노 및 마이크로 스크래치 테스트는 기존의 경도 등급을 훨씬 뛰어넘는 실제 내구성에 대한 반복 가능한 데이터 기반 인사이트를 제공합니다.

ℹ️ 자세히 알아보기 코팅 및 화면 보호기용 스크래치 및 접착력 테스트 서비스입니다.

스크래치 테스트 목표:
화면 보호기의 고장 부하 측정하기

이 연구의 목적은 나노베아 PB1000 기계식 테스터가 폴리머 및 유리 화면 보호기 모두에 대해 반복 가능하고 표준화된 스크래치 저항 테스트를 수행하는 방법을 입증하는 것입니다. 이 시스템은 적용된 하중을 점진적으로 증가시킴으로써 응집력 및 접착 실패에 대한 임계 하중을 감지하고 음향 방출 신호를 캡처하며 이러한 이벤트를 스크래치 깊이, 마찰력 및 표면 변형과 상호 연관시킵니다.

이 방법론은 각 보호 코팅의 완전한 기계적 프로파일을 제공하여 제조업체와 R&D 팀이 제품 성능 향상을 위해 재료 배합, 코팅 접착 강도, 표면 내구성 및 최적의 코팅 두께를 평가할 수 있도록 합니다. 이러한 스크래치 평가는 나노베아의 광범위한 제품군의 일부입니다. 기계 테스트 솔루션 R&D, 품질 관리 및 생산 환경 전반에서 코팅, 필름 및 기판의 특성을 분석하는 데 사용됩니다.

나노비아 PB1000 대형 플랫폼
기계 테스터

스크래치 테스트 파라미터 및 계측기 설정

TPU 및 강화유리 화면 보호기의 스크래치 저항성 평가는 반복성과 정확한 고장 하중 감지를 보장하기 위해 통제된 조건에서 수행되었습니다. 다음 매개변수는 나노베아 PB1000 기계식 테스터에 사용된 점진적 부하 스크래치 테스트 설정을 정의합니다.

로드 유형	프로그레시브
초기 로드	0.1 N
최종 로드	12 N
슬라이딩 속도	3.025mm/min
슬라이딩 거리	3mm
들여쓰기 기하학	로크웰(120° 원뿔)
들여쓰기 재료(팁)	다이아몬드
들여쓰기 팁 반경	50 µm
대기권	AIR
온도	24°C(실온)

표 1: 스크래치 테스트에 사용되는 테스트 매개변수

프로그레시브 하중 스크래치 측정 중 NANOVEA PB1000 기계식 테스터에 장착된 화면 보호기 샘플.

스크래치 방지 테스트에 사용되는 화면 보호기 샘플

스크래치 저항성, 고장 동작 및 기계적 내구성의 차이를 비교하기 위해 시중에서 판매되는 두 가지 화면 보호기 소재를 선택했습니다. 일관되고 편향되지 않은 비교를 위해 두 샘플을 NANOVEA PB1000 기계식 테스터에 단단히 장착하고 동일한 점진적 부하 조건에서 평가했습니다.

TPU 화면 보호기는 탄성은 높지만 내마모성이 낮은 유연한 고분자 필름이며, 강화 유리 보호기는 경도가 높고 충격 보호 기능이 강화되도록 설계된 단단하고 깨지기 쉬운 소재를 나타냅니다. 동일한 하중 프로파일에서 두 소재를 테스트하면 소재 구성, 탄성 및 경도가 스크래치 고장 모드에 미치는 영향을 명확하게 평가할 수 있습니다.

TPU 화면 보호기

강화 유리

그림 1: 긁힘 방지 테스트를 위해 준비된 TPU 및 강화 유리 화면 보호기.

스크래치 테스트 결과: TPU와 강화유리 화면 보호기의 고장 모드 비교

화면 보호기 유형	임계 부하 #1(N)	임계 부하 #2 (N)
TPU	n/a	2.004 ± 0.063
강화 유리	3.608 ± 0.281	7.44 ± 0.995

표 2: 각 화면 보호기 샘플에 대한 임계 부하 요약.

TPU와 강화유리 화면 보호기는 근본적으로 다른 기계적 특성을 가지고 있기 때문에 각 샘플은 점진적 하중 스크래치 테스트 중에 뚜렷한 고장 모드와 임계 하중 임계값을 나타냈습니다. 표 2에는 각 소재에 대해 측정된 임계 하중이 요약되어 있습니다.

임계 하중 #1은 균열 시작 또는 방사형 골절과 같이 광학 현미경으로 관찰 가능한 응집 실패의 첫 번째 지점을 나타냅니다.

임계 부하 #2는 음향 방출(AE) 모니터링을 통해 감지된 첫 번째 주요 이벤트에 해당하며, 일반적으로 더 큰 구조적 고장 또는 침투 이벤트를 나타냅니다.

TPU 화면 보호기 - 유연한 폴리머 동작

TPU 화면 보호기는 단 한 번의 중요한 중요 이벤트(중요 하중 #2)만 나타났습니다. 이 하중은 스크래치 트랙을 따라 필름이 휴대폰 화면 표면에서 들어 올려지거나 벗겨지거나 박리되기 시작한 지점에 해당합니다.

임계 하중 #2(≈2.00N)를 초과하면 압자가 충분히 관통하여 나머지 테스트 기간 동안 휴대폰 화면에 직접 스크래치가 생겼습니다. 소재의 높은 탄성과 낮은 응집력으로 인해 별도의 임계 하중 #1 이벤트는 감지되지 않았습니다.

강화 유리 화면 보호기 - 깨지기 쉬운 고장 동작

강화유리 화면 보호기는 깨지기 쉬운 소재의 특징인 두 가지 임계 하중을 보여주었습니다:

임계 하중 #1(≈3.61N): 현미경으로 방사형 골절 및 균열 시작이 관찰되어 유리 층의 조기 응집 실패를 나타냅니다.
임계 하중 #2(≈7.44N): 큰 AE 스파이크와 스크래치 깊이의 급격한 증가는 더 높은 하중에서 프로텍터 관통을 나타냅니다.

AE 강도는 TPU보다 높았지만 휴대폰 화면에 손상이 전달되지 않아 강화유리 보호기가 치명적인 고장 전에 하중을 흡수하고 분산하는 능력을 입증했습니다.

두 재료 모두에서 임계 하중 #2는 압자가 화면 보호기를 뚫는 순간에 해당하여 각 샘플의 보호 한계를 확인했습니다.

TPU 화면 보호기: 스크래치 테스트 데이터 및 고장 분석

스크래치	임계 부하 #2 (N)
1	2.033
2	2.047
3	1.931
평균	2.003
표준 편차	0.052

표 3: TPU 화면 보호기 스크래치 테스트 중 측정된 임계 하중.

그림 2: TPU 화면 보호기의 마찰력, 정상 하중, 음향 방출(AE), 스크래치 깊이 대 스크래치 길이를 측정합니다. (B) 임계 부하 #2

그림 3: 임계 부하 #2(5배율, 이미지 폭 0.8934mm)에서의 TPU 화면 보호기 광학 현미경 이미지.

그림 4: 점진적 부하 테스트 후 전체 스크래치 트랙을 보여주는 TPU 화면 보호기의 스크래치 후 전체 길이 이미지입니다.

강화유리 화면 보호기: 임계 하중 데이터 및 파손 거동

스크래치	임계 부하 #1(N)	임계 부하 #2 (N)
1	3.923	7.366
2	3.382	6.483
3	3.519	8.468
평균	3.653	6.925
표준 편차	0.383	0.624

표 4: 강화유리 화면 보호기 스크래치 테스트 중 측정한 임계 하중입니다.

ℹ️ 비규산염 폴리머 코팅과 비교하려면 다음 연구를 참조하십시오. PTFE 코팅 마모 테스트, 는 유사한 점진적 하중 조건에서 저마찰 폴리머 필름의 고장 거동을 강조합니다.

그림 5: 강화유리 화면 보호기의 마찰력, 정상 하중, 음향 방출(AE), 스크래치 깊이 대 스크래치 길이를 측정합니다. (A) 임계 부하 #1 (B) 임계 부하 #2

그림 6: 5배 확대(이미지 폭: 0.8934mm)에서 임계 부하 #1(왼쪽) 및 임계 부하 #2(오른쪽)의 고장 위치를 보여주는 광학 현미경 이미지.

그림 7: 강화 유리 스크래치 트랙의 테스트 후 광학 현미경 이미지, 점진적 하중 테스트 후 골절 시작(CL#1)과 최종 관통 영역(CL#2)을 강조 표시합니다.

결론: TPU와 강화유리 화면 보호기의 스크래치 성능 비교

이 연구는 나노베아 PB1000 기계식 테스터가 점진적 하중 및 음향 방출(AE) 감지를 사용하여 제어되고 반복 가능하며 매우 민감한 스크래치 저항 측정을 제공하는 방법을 보여줍니다. 이 시스템은 응집 및 접착 실패 이벤트를 모두 정확하게 포착함으로써 기계적 스트레스가 증가함에 따라 TPU 및 강화 유리 화면 보호기가 어떻게 작동하는지를 명확하게 비교할 수 있습니다.

실험 결과에 따르면 강화 유리는 TPU보다 훨씬 높은 임계 하중을 견디며 우수한 스크래치 저항성, 지연된 파손 시작, 압흔 침투에 대한 안정적인 보호 기능을 제공하는 것으로 나타났습니다. TPU는 응집 강도가 낮고 박리가 일찍 일어나기 때문에 스트레스가 많은 환경에서는 한계가 있습니다.

장애 부하를 식별한 후 결과 스크래치 트랙을 다음을 사용하여 분석할 수도 있습니다. 비접촉식 3D 광학 프로파일로미터 를 사용하여 홈 깊이, 잔류 변형 및 스크래치 후 지형을 측정합니다. 이를 통해 각 소재의 기계적 프로파일을 완성할 수 있습니다.

나노베아 기계식 테스터는 정확하고 반복 가능한 압흔, 스크래치 및 마모 테스트를 위해 설계되었으며 ISO 및 ASTM을 준수하는 나노 및 마이크로 모듈을 지원합니다. 다양한 기능을 갖추고 있어 R&D, 생산 및 품질 관리 전반에 걸쳐 박막, 코팅, 폴리머, 유리 및 기판의 전체 기계적 프로파일을 평가하는 데 이상적인 솔루션입니다.

자주 묻는 질문
스크래치 내성 테스트 정보

스크래치 저항 테스트란 무엇인가요?

스크래치 저항 테스트는 다이아몬드 스타일러스에 점진적으로 증가하는 하중을 가했을 때 소재나 코팅이 어떻게 반응하는지를 평가합니다. 이 테스트는 응집력 또는 접착 실패가 발생하는 임계 하중을 식별하여 내구성, 접착 강도 및 표면 손상에 대한 저항성을 정량화할 수 있는 척도를 제공합니다.

접착 실패와 접착 실패의 차이점은 무엇인가요?

응집 실패 발생 내 코팅이나 재료에 균열, 찢어짐, 내부 파손 등의 문제가 발생할 수 있습니다.
접착 실패는 코팅이 인쇄물에서 분리될 때 발생하며, 이는 접착 강도가 충분하지 않음을 나타냅니다.

나노베아 PB1000은 동기화된 음향 방출 모니터링, 스크래치 깊이 추적 및 마찰 분석을 사용하여 이 두 가지를 모두 감지합니다.

수동 방식 대신 기계식 테스터를 사용하는 이유는 무엇인가요?

나노베아 PB1000과 같은 기계식 테스터는 정밀하고 반복 가능하며 표준화된 측정을 제공하여 R&D, 생산 검증 및 품질 관리를 위한 신뢰할 수 있는 데이터를 보장합니다. 또한 음향 방출 감지 및 실시간 깊이 모니터링과 같은 고급 기능을 제공하여 수동 방식으로는 제공하지 못하는 기능을 제공합니다.

소재에 대한 신뢰할 수 있는 스크래치 테스트가 필요하신가요?

The post Scratch Resistance Testing of Phone Screen Protectors appeared first on NANOVEA: Advanced Profilometers, Tribometers, Nanoindenters, and Scratch Testers for Materials Testing.

나노베아 트라이보미터를 이용한 암석 마모도 테스트

nanovea — 2023년 9월 13일 수요일 17:07:17 +0000

암반 마찰학:나노비아 마찰계(Tribometer)를 이용한 암석 마모성 시험

작성자

DUANJIE LI, PhD

소개

암석은 광물 알갱이로 구성되어 있습니다. 이러한 광물의 종류와 풍부함, 그리고 광물 알갱이 사이의 화학적 결합 강도가 암석의 기계적, 마찰학적 특성을 결정합니다. 지질 암석 주기에 따라 암석은 변형을 겪을 수 있으며 일반적으로 화성암, 퇴적암, 변성암의 세 가지 주요 유형으로 분류됩니다. 이러한 암석은 다양한 광물 및 화학적 조성, 투과성 및 입자 크기를 나타내며 이러한 특성은 다양한 내마모성에 기여합니다. 암석 마찰학은 다양한 지질 및 환경 조건에서 암석의 마모 및 마찰 거동을 탐구합니다.

암석 연마재 시험의 중요성

마모 및 마찰을 포함한 암석에 대한 다양한 유형의 마모는 유정 굴착 과정에서 발생하며, 이는 드릴 비트 및 절단 도구의 수리 및 교체로 인해 직접적이고 결과적으로 상당한 손실을 초래합니다. 따라서 암석의 천공성, 천공성, 절단성 및 마모성에 대한 연구는 석유, 가스 및 광업 산업에서 매우 중요합니다. 암석 마찰학 연구는 가장 효율적이고 비용 효과적인 시추 전략을 선택하는 데 중추적인 역할을 하여 전반적인 효율성을 향상시키고 재료, 에너지 및 환경 보존에 기여합니다. 또한 표면 마찰을 최소화하면 드릴 비트와 암석 사이의 상호 작용을 줄여 도구 마모를 줄이고 드릴링/절단 효율을 향상시키는 데 매우 유리합니다.

측정 목표

본 연구에서는 두 종류의 암석에 대한 마찰 특성을 시뮬레이션하고 비교하여 나노비아 T50 마모 시험기 통제되고 모니터링되는 방식으로 암석의 마찰 계수와 마모율을 측정합니다.

나노비아 T50 컴팩트
자유 중량 트라이보미터

샘플

테스트 절차

두 암석 샘플의 마찰 계수, COF 및 내마모성은 Pin-on-Disc 마모 모듈을 사용하는 NANOVEA T50 마찰계로 평가되었습니다. Al2O3 볼(직경 6mm)을 카운터 재료로 사용했습니다. 테스트 후 NANOVEA 비접촉 프로파일로미터를 사용하여 마모 트랙을 검사했습니다. 테스트 매개변수는 아래에 요약되어 있습니다.

마모율 K는 공식 K=V/(F×s)=A/(F×n)을 사용하여 평가되었으며, 여기서 V는 마모량, F는 일반 하중, s는 슬라이딩 거리, A는 마모 트랙의 단면적, n은 회전수입니다. NANOVEA Optical Profilometer를 사용하여 표면 거칠기와 마모 트랙 프로파일을 평가하고 광학 현미경을 사용하여 마모 트랙 형태를 검사했습니다.

본 연구에서는 카운터 재료로 Al2O3 볼을 예로 사용했습니다. 실제 적용 상황을 시뮬레이션하기 위해 맞춤형 고정 장치를 사용하여 다양한 모양의 견고한 재료를 적용할 수 있습니다.

테스트 매개변수

샘플	석회석, 대리석
마모 반지름	5mm
일반 힘	10 N
테스트 기간	10 분
속도	100rpm

결과 및 토론

NANOVEA Mechanical Tester의 Micro Indentation 모듈을 활용하여 석회석과 대리석 샘플의 경도(H)와 탄성 계수(E)를 그림 1에서 비교합니다. 석회석 샘플은 H에 대해 1.07, E에 대해 49.6GPa의 값을 기록한 대리석과 달리 각각 0.53 및 25.9GPa로 측정된 더 낮은 H 및 E 값을 나타냈습니다. 석회석 샘플은 과립화 및 다공성 특성으로 인해 표면 불균질성이 더 크기 때문일 수 있습니다.

두 암석 샘플의 마모 테스트 중 COF의 변화는 그림 2에 나와 있습니다. 석회석은 초기에 마모 테스트 시작 시 COF가 약 0.8로 급격히 증가하여 테스트 기간 동안 이 값을 유지합니다. COF의 이러한 급격한 변화는 마모 트랙 내의 접촉면에서 발생하는 빠른 마모 및 거칠기 과정으로 인해 Al2O3 볼이 암석 샘플에 침투하기 때문일 수 있습니다. 대조적으로, 대리석 샘플은 약 5m의 슬라이딩 거리 후에 COF가 더 높은 값으로 눈에 띄게 증가하여 석회석과 비교할 때 내마모성이 우수함을 나타냅니다.

그림 1: 석회암과 대리석 시료의 경도 및 영의 계수 비교.

그림 2: 마모 테스트 중 석회석 및 대리석 샘플의 마찰계수(COF) 변화.

그림 3은 마모 테스트 후 석회석과 대리석 샘플의 단면 프로파일을 비교하고 표 1은 마모 추적 분석 결과를 요약합니다. 그림 4는 광학 현미경으로 관찰한 샘플의 마모 흔적을 보여줍니다. 마모 트랙 평가는 COF 진화 관찰과 일치합니다. 장기간 동안 낮은 COF를 유지하는 대리석 샘플은 석회석의 0.0353mm³/Nm에 비해 0.0046mm³/Nm의 더 낮은 마모율을 나타냅니다. 대리석의 우수한 기계적 특성은 석회석보다 내마모성이 우수합니다.

그림 3: 마모 트랙의 단면 프로파일.

표 1: 마모궤적 분석 결과 요약.

그림 4: 광학 현미경으로 트랙을 착용합니다.

결론

본 연구에서 우리는 제어되고 모니터링되는 방식으로 대리석과 석회석이라는 두 암석 샘플의 마찰 계수와 내마모성을 평가하는 NANOVEA 마찰계의 성능을 보여주었습니다. 대리석의 우수한 기계적 특성은 뛰어난 내마모성에 기여합니다. 이러한 특성으로 인해 석유 및 가스 산업에서 드릴링 또는 절단 작업이 어려워집니다. 반대로, 바닥타일 등 고급 건축자재로 사용하면 수명이 대폭 연장됩니다.

NANOVEA 마찰계는 회전 모드와 선형 모드 모두에서 ISO 및 ASTM 표준을 준수하면서 정확하고 반복 가능한 마모 및 마찰 테스트 기능을 제공합니다. 또한 고온 마모, 윤활 및 마찰 부식을 위한 옵션 모듈을 제공하며 모두 하나의 시스템에 원활하게 통합됩니다. NANOVEA의 탁월한 제품군은 얇거나 두꺼운, 부드럽거나 단단한 코팅, 필름, 기판 및 암석 마찰학의 모든 범위의 마찰공학 특성을 결정하는 데 이상적인 솔루션입니다.

비슷한 애플리케이션이 있으신가요?

The post Rock Abrasivity Testing with NANOVEA Tribometer appeared first on NANOVEA: Advanced Profilometers, Tribometers, Nanoindenters, and Scratch Testers for Materials Testing.

Shot Peened 표면 분석

nanovea — 2023년 8월 16일 수요일 14:19:21 +0000

숏핀 표면 분석

3D 비접촉식 프로파일로미터 사용

작성자

크레이그 레싱

소개

쇼트 피닝은 기판에 구형 금속, 유리 또는 세라믹 비드(일반적으로 "샷"이라고 함)를 표면에 가소성을 유도하기 위한 힘으로 충격을 가하는 공정입니다. 피닝 전후의 특성을 분석하면 프로세스 이해 및 제어를 향상시키는 데 중요한 통찰력을 얻을 수 있습니다. 샷에 의해 남겨진 딤플의 표면 거칠기와 적용 범위는 특히 주목할 만한 측면입니다.

숏핀 표면 분석을 위한 3D 비접촉 프로파일로미터의 중요성

전통적으로 샷 피닝된 표면 분석에 사용되었던 기존 접촉식 프로파일로미터와 달리 3D 비접촉식 측정은 완전한 3D 이미지를 제공하여 적용 범위와 표면 지형에 대한 보다 포괄적인 이해를 제공합니다. 3D 기능이 없으면 검사는 2D 정보에만 의존하게 되므로 표면 특성화에 충분하지 않습니다. 지형, 적용 범위 및 거칠기를 3D로 이해하는 것이 피닝 공정을 제어하거나 개선하기 위한 최선의 접근 방식입니다. 나노베아의 3D 비접촉 프로파일로미터 가공된 표면과 피닝된 표면에서 발견되는 가파른 각도를 측정하는 고유한 기능을 갖춘 Chromatic Light 기술을 활용합니다. 또한 프로브 접촉, 표면 변화, 각도 또는 반사율로 인해 다른 기술이 신뢰할 수 있는 데이터를 제공하지 못하는 경우 NANOVEA Profilometer가 성공합니다.

측정 목표

이 응용 분야에서 NANOVEA ST400 비접촉식 프로파일로미터는 비교 검토를 위해 원료와 두 개의 서로 다른 피닝 표면을 측정하는 데 사용됩니다. 3D 표면 스캔 후 자동으로 계산할 수 있는 끝없는 표면 매개변수 목록이 있습니다. 여기에서는 3D 표면을 검토하고 거칠기, 딤플 및 표면적을 정량화하고 조사하는 것을 포함하여 추가 분석을 위해 관심 영역을 선택합니다.

나노비아 ST400 표준
광학 3D 프로파일로미터

샘플

결과

강철 표면

ISO 25178 3D 조도 매개변수

SA	0.399㎛	평균 거칠기
Sq	0.516㎛	RMS 거칠기
Sz	5.686μm	최대 피크-밸리
Sp	2.976μm	최대 피크 높이
Sv	2.711μm	최대 피트 깊이
SKU	3.9344	첨도
Ssk	-0.0113	기울기
남자 이름	0.0028mm	자동 상관 길이
Str	0.0613	텍스처 종횡비
스다르	26.539mm²	표면적
Svk	0.589㎛	감소된 계곡 깊이

결과

피닝된 표면 1

표면 커버리지 98.105%

ISO 25178 3D 조도 매개변수

Sa	4.102㎛	평균 거칠기
Sq	5.153㎛	RMS 거칠기
Sz	44.975μm	최대 피크-밸리
Sp	24.332㎛	최대 피크 높이
Sv	20.644μm	최대 피트 깊이
SKU	3.0187	첨도
Ssk	0.0625	기울기
남자 이름	0.0976mm	자동 상관 길이
Str	0.9278	텍스처 종횡비
스다르	29.451mm²	표면적
Svk	5.008μm	감소된 계곡 깊이

결과

피닝된 표면 2

표면 커버리지 97.366%

ISO 25178 3D 조도 매개변수

Sa	4.330㎛	평균 거칠기
Sq	5.455㎛	RMS 거칠기
Sz	54.013㎛	최대 피크-밸리
Sp	25.908μm	최대 피크 높이
Sv	28.105μm	최대 피트 깊이
SKU	3.0642	첨도
Ssk	0.1108	기울기
남자 이름	0.1034mm	자동 상관 길이
Str	0.9733	텍스처 종횡비
스다르	29.623mm²	표면적
Svk	5.167μm	감소된 계곡 깊이

결론

이 숏 피닝 표면 분석 애플리케이션에서 우리는 NANOVEA ST400 3D 비접촉식 프로파일러가 피닝 표면의 지형과 나노미터 세부 사항을 모두 정확하게 특성화하는 방법을 시연했습니다. 표면 1과 표면 2 모두 원료와 비교할 때 여기에 보고된 모든 매개변수에 상당한 영향을 미친다는 것이 분명합니다. 이미지를 간단하게 육안으로 검사하면 표면 간의 차이를 알 수 있습니다. 이는 커버리지 영역과 나열된 매개변수를 관찰하여 추가로 확인됩니다. 표면 2와 비교하여 표면 1은 더 낮은 평균 거칠기(Sa), 더 얕은 찌그러짐(Sv) 및 감소된 표면적(Sdar)을 나타내지만 커버리지 영역은 약간 더 높습니다.

이러한 3D 표면 측정에서 관심 영역을 쉽게 식별하고 거칠기, 마감, 질감, 모양, 지형, 편평도, 뒤틀림, 평면도, 부피, 계단 높이 등을 포함한 포괄적인 측정을 수행할 수 있습니다. 자세한 분석을 위해 2D 단면을 빠르게 선택할 수 있습니다. 이 정보를 통해 표면 측정 리소스의 전체 범위를 활용하여 피닝된 표면을 포괄적으로 조사할 수 있습니다. 통합 AFM 모듈을 사용하여 특정 관심 영역을 추가로 검사할 수 있습니다. NANOVEA 3D 프로파일로미터는 최대 200mm/s의 속도를 제공합니다. 크기, 속도, 스캔 기능 측면에서 사용자 정의할 수 있으며 클래스 1 클린룸 표준도 준수할 수 있습니다. 인라인 또는 온라인 사용을 위한 인덱싱 컨베이어 및 통합과 같은 옵션도 사용할 수 있습니다.

본 문서에 제시된 샘플을 제공해 주신 IMF의 헤이든 씨께 특별히 감사드립니다. 산업 금속 마감 처리 주식회사 | indmetfin.com

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