On the load-displacement relation of the second order polynomial indenter

In the nanoindentation data analysis, sharp indenters are often modeled as conical indenters, and blunt indenters are often treated as spheres, or parabolic indenters. For an axisymmetric indenter whose shape is neither conical nor spherical, a second order polynomial indenter may be a good approximation. In this paper, the relations among the load, the depth of the penetration and the radius of the contact area of a second order polynomial indenter are presented. It shows that the power-law assumption of the load-displacement relation is not always valid. (c) 2007 Elsevier B.V. All rights reserved.