Extending the contact regimes to single-crystal indentations

Abstract

This article provides a fresh look into the concept of the contact regimes in mechanistic analyses of indentation experiments performed in single crystals. In this context, spherical microindentation experiments in fcc metals are examined through detailed continuum crystal plasticity finite element simulations in order to provide meaning to the onset of fully-plastic and elasto-plastic contact regimes, which are well-known to rule the behavior of polycrystals exhibiting isotropic uniaxial stress–strain curves. Attention is then given to evaluate the applicability of Taborʼs hardness relation in ruling fully-plastic single-crystal spherical indentations as well as the extraction of the uniaxial plastic flow properties from a series of microindentation tests performed at different penetrations. A discussion is finally provided on the applicability of self-similarity assumptions to the analysis of single-crystal fully-plastic indentations.