ELASTIC PLASTIC CONTACT OF SURFACES CONSIDERING ELLIPSOIDAL ASPERITIES OF WORK-HARDENING MULTIPHASE MATERIALS

The importance of the plasticity index for defining the degree of elastic and plastic deformation of surface asperities is described. Some experimental validation of the argument is provided and the method is extended to cover the case of ellipsoidal asperity contacts and the effect of work-hardening for a general asperity height probability distribution. It is also shown how the model may be applied to study the behaviour of multi-phase composites. The arguments are based on Hertzian contacts without tractions but may be used with reasonable confidence for contacts where the coefficient of friction is less than 0.1.