Determination of unique plastic properties from sharp indentation

A method is proposed which allows for the unique determination of Young's modulus E, strength coefficient K and strain hardening exponent n (Lunwix power-law) from given load-displacement curves (P-h curves). The method is based on analytically and numerically (FEM) derived relationships between the material parameters (E, K and n) and the indentation results (C and W-el/W-tot). It is shown that in case of a known Young's modulus a single P-h curve of a self-similar indenter contains sufficient information for the unique determination of K and n. Is the Young's modulus not a priori known an additional P-h curve is required for the unique determination of all three material parameters. The proposed method was subsequently numerically verified for so-called mystical materials (Chen et al., 2007). (C) 2019 Elsevier Ltd. All rights reserved.