A numerical simulation of fretting wear profile taking account of the evolution of third body layer

In this paper we propose a new Finite Element Modeling (FEM) strategy to simulate fretting wear profiles, taking account of the presence of a third body layer evolving over time. To validate this approach, the simulations were compared to experimental results on a gross slip Ti-6Al-4V cylinder/plane interface. A simple experimental procedure based on adequate superimposition of worn surface profiles allowed the estimation of individual cylinder and plane friction energy wear rates and quantification of the thickness of the third body embedded within the interface. A third body conversion factor, expressing the proportion of worn thickness transferred to the third body layer at a given position in the fretted interface was developed. The various quantitative variables were introduced in a coupled Matlab-Python-Abaqus algorithm where the worn thickness of counterfaces was simulated using a friction energy wear approach while the third body layer was progressively established by loading a “bell” thickness profile. The constant (γ) and parabolic distribution (γx) of third body conversion factors were examined. Quantitative comparison with experimental results confirmed the interest of this new numerical strategy. Maximum wear depth, which was underestimated by nearly −80% using the wear model without taking account of the third body, was perfectly predicted, with error less than 10%, using the γx third body model. Comparison with longer tests, up to 30,000 fretting cycles, confirmed the stability of the approach which, in addition to providing very good prediction of fretting scar profiles allows more conservative prediction of fretting crack risk.