435 Constitutive Equation Determination with Indentation Technique using Spherical Indenter

Abstract

The indentation test using a spherical indenter and the inverse analysis on the load-depth curve obtained from the indentation test using an FEM code were performed to identify the constitutive equation of the surface layer of materials. The identified constitutive equation is well describable on the uniaxial tensile behavior. The technique was applied to evaluate the material degradation of 316ss due to mercury corrosion. The constitutive equation of the corroded surface layer exhibits that the yield stress σ_y becomes larger and the work-hardening coefficient n smaller than the as-received one and the embrittlement due to mercury corrosion.