A dynamical FEA fretting wear modeling taking into account the evolution of debris layer

A new Finite Element Analysis (FEA) strategy is developed to simulate fretting wear, taking into account the evolution of the debris layer trapped in the interface, so called "third body". To validate this approach, simulations were compared to experimental results from gross slip Ti-6Al-4V cylinder/plane experiments. Adequate worn surface analyses allow the estimation of both cylinder and plane friction energy wear rates and the debris layer thickness evolution. A third body conversion factor (gamma(x)), expressing the proportion of worn thickness transferred to the third body layer (i.e. debris layer) at a given position in the fretted interface is introduced. A coupled Matlab-Python-Abaqus algorithm is developed to simulate the surface wear on plane and cylinder surfaces to formalize the continuous evolution of the debris layer trapped within interface. Quantitative comparisons with experimental results confirmed the interest of this FEA approach. The maximum wear depth, which was underestimated by nearly 80% without considering the third body, is predicted with an error less than 10%. A numerical investigation demonstrates that the elastic properties of the third body do not influence the surface wear profile. Acting as a contact pressure concentrator, the third body effect appears more geometrical than rheological. This third body FEA fretting wear modeling is extended in order to consider both test duration and sliding amplitude effects. Rather good correlations with experiments confirm the interest of this approach.