Effects of indenter geometry and material properties on the correction factor of Sneddon’s relationship for nanoindentation of elastic and elastic–plastic materials

Finite element simulations of indentations on elastic and elastic–plastic materials have been performed to systematically study the effects of indenter geometry and mechanical properties, namely Poisson’s ratio and the E/σy ratio, on the correction factor for Sneddon’s equation used for analysis of nanoindentation data. Two indenter geometries, namely conical and Berkovich indenters, have been considered. It has been shown that the first-order correction for conical indentation on elastic materials previously developed by Hay et al. [Hay JC, Bolshakov A, Pharr GM. J Mater Res 1999;14:2296–305] can be applied only to conical indentation of elastic deformation-dominated materials but not to Berkovich indentation. A new general relationship for the estimation of the correction factor for Berkovich indentation is proposed based on the finite element simulation results. This relationship gives a better estimation of correction factor for Berkovich indentations on both elastic and elastic–plastic materials.