A simple predictive model for spherical indentation

A simple model is described with which the entire force versus penetration behavior of indentation with a sphere, during loading and unloading, may be simulated from knowledge of the four test material parameters, Young's modulus, Poisson's ratio, flow stress at the onset of full plastic flow and strain hardening index, and the elastic properties of the indenter. The underlying mechanisms are discussed and the predictions of the model are compared with data produced by an ultra low load, penetration measuring instrument.