Corrosion Effect On Hardness Using Nanoindentation
The mechanical properties of materials deteriorate during the corrosion process. For example, lepidocrocite (γ-FeOOH) and goethite (α-FeOOH) form in the atmospheric corrosion of carbon steel. Their loose and porous nature results in absorption of moisture and in turn further acceleration of the corrosion process. Akaganeite (β-FeOOH), another form of iron
oxyhydroxide, is generated on the steel surface in chloride containing environments. Nanoindentation can control the indentation depth in the range of nanometers and microns, making it possible to quantitatively measure the hardness and Young’s modulus of the corrosion products formed on the metal surface. It provides physicochemical insight in corrosion mechanisms involved so as to select the best candidate material for the target applications.