Study of the rate-dependent behavior of pure nickel in conical nanoindentation through numerical simulation coupled to experiments

The use of specific metallic materials in micro-mechanical systems is promising for surgical applications due to their bio-compatibility and interesting mechanical and wear properties compared to the widely used material, silicon. Nanoindentation is one of the methods used to investigate the mechanical properties of materials at the nano-scale. Numerical simulation tools are useful in the understanding of the nanoindentation experiment. In this paper, the results of numerical simulations coupled to nanoindentation experiments conducted at various indentation depths and at different load rates on pure nickel are presented. The study parameters are carefully chosen to ensure the closest possible conditions between the experiments and the numerical simulations, It is shown that a good agreement between the experimental and the numerical results can be obtained for both the load levels and the creep indentation phase (displacement-time curves in the holding period) when taking into account a simple model with rate-dependent material behavior, and using a material parameter set that is in the acceptable domain for metals. (C) 2008 Elsevier Ltd. All rights reserved.