Elastic–plastic analysis of a punch and its equivalent notch under fretting conditions

The main objective of this paper is to analyse the elastic–plastic behaviour of a mechanical system consisting of a square flat sharp-edged punch in contact with a half-plane of the same material under fretting conditions. The influence of the local yield effects and the material contact on the stress and strain fields is evaluated and the results compared with those of some simplified models. The results obtained from this model are compared with two similar models with the following changes: (1) in one, the contact is replaced by a material continuity; and (2) in the other, the elastic–plastic material is replaced by a completely elastic material. The purpose of the first comparison is to determine the range of fretting conditions within which is acceptable to substitute the split specimen in the fretting tests with a continuous one, as suggested by Mugadu and Hills (2002 [1]). The second comparison is used to assess the validity of the small-scale yielding hypothesis for fretting conditions.

► We study the elastic–plastic mechanical behaviour around the singularity of a complete contact problem.
► Two simplifications of the problem are compared with the elastic–plastic contact solution.
► The plasticity plays a major role on the mean stresses around the punch corners.
► For high or middle loads, the elastic approximation does not seem to be suitable for fatigue predictions.
► For high or middle loads, continuous specimens are suitable for fatigue life predictions.