Contact size effect on fretting wear behaviour: application to an AISI 52100/AISI 52100 interface

Abstract

AbstractFretting situations are becoming increasingly important for industrial applications. Fretting wear is defined as a small oscillatory displacement between two contacting bodies. The interface is damaged by debris generation and its ejection from the contact area. In this work, investigations on AISI 52100 steel self‐mated contacts with a ball on flat configuration under dry conditions have been carried out. Fretting tests at a constant maximum Hertzian pressure of 1.1 GPa for different ball diameters have been performed to cover a huge range of contact sizes. A specific experimental procedure is considered to discriminate between the relative impact of the sliding amplitude and the contact size effect. It is shown that a single parameter cannot capture the total interface behaviour. Indeed, an asymptotic decrease in the friction coefficient and wear rate versus the contact size is observed. The increase in the contact area accentuates the implication of third body in the interface. The larger the contact size, the more difficult the debris ejection, the higher the third‐body accommodation, and the lower the coefficient of friction and wear rates. A simple power function is introduced to formalise friction and wear behaviours. Copyright © 2009 John Wiley & Sons, Ltd.