Reverse analysis of nano-indentation using different representative strains and residual indentation profiles

This study was designed to minimize the sensitivity of the data and experimental errors and to improve the accuracy in the reverse analysis of nano-indentation. This work was accomplished by using the various representative strains in a generalization of the loading curvature C and adopting only C and Wp/Wt as the independent parameters representing P–h curve in establishing a series of dimensionless functions. Finite element simulations of nano-indentation were performed for 140 combinations of each parameter (E, σy, n, ν) expressing the elastic–plastic behaviors of the universal engineering metals. The dimensionless functions established from the computational results were examined with different materials (Al6061-T6, AISI 1010, 1045 and copper (99%)). Finally, the relation between the residual indentation profiles and the strain hardening exponents of the indented materials was briefly investigated to verify the reliability of the reverse analysis.