Experimental and modelling aspects of abrasive wear of a A357 aluminium alloy under gross slip fretting conditions

Under fretting loadings, material damage is often linked to sliding conditions. Generally, wear prevails when the gross slip regime is established. To investigate the wear response of A357 aluminium alloy against an AISI 52100 steel, such fretting loadings have been reproduced through a simple sphere/plane contact configuration. A parabolic evolution of the wear kinetics with the applied sliding amplitude is observed. Since hypotheses based on the temperature effect and sliding velocity influence are powerless to explain this evolution, mechanical analyses are undertaken. Both analytical and FEM development are used to identify the mechanical description of the investigated case. It was shown that elasto-plastic shakedown and accumulated plastic dissipation hypotheses cannot explain the sliding dependence of the wear rate. More in-depth investigations infer that this wear evolution could be related to an increase of the debris ejection rate with the applied sliding amplitude. Hence, a modified Archard approach taking into account the debris ejection process is introduced to formalize the tribo-system wear kinetics.