Finite element modelling of fretting wear surface evolution: Application to a Ti-6Al-4V contact

Fretting is defined as a small displacement oscillatory motion between two solids in contact. Depending on the loading conditions (displacement amplitude, normal force, etc.) fretting damage can be induced by surface adhesion, abrasion, and fatigue with debris formation and ejection being the by products of wear. For the studied titanium alloy Ti-6Al-4V, fretting conditions were reproduced through a simple cylinder on plane contact. By introducing an energy wear concept, the relative impact of pressure sliding amplitude and number of fretting cycles can be rationalized through a single parameter. Predicting wear kinetics as well as geometrical changes of the wear scar under fretting conditions appears to be of great interest for industrial applications, so a specific numerical method to model the progressive evolution of the wear scar is developed. This method, based on a finite element analysis combined with global experimental wear kinetics, allows the modification of nodal coordinates to simulate material removal. This approach is then validated by comparing numerical and experimental results. Finally, these results are discussed and further investigations are outlined. (C) 2007 Elsevier B.V. All rights reserved.