A Critical Investigation on the Nature of Material Dependency of Elastic-Plastic Contact Behavior

This work attempts to make an investigation on the nature of material dependency of elastic-plastic contact behavior through a more accurate contact analysis between a deformable sphere and a rigid flat by finite element method. Analysis is carried out beyond elastic limit, till the inception of plasticity for various materials with different radii. It is found those materials with Young’s modulus to yield stress (E/Y) ratio less than 300 show strikingly different contact phenomena. Equation for hardness in terms of E/Y ratio for these materials is presented. A proposal for fixing the point of attaining fully plastic state is suggested. Existing disagreement over the dependency of hardness on material properties is critically examined.