The application of fretting wear modelling to a spline coupling

The prediction of fretting wear is a significant issue for the design of high-performance aeroengine spline couplings, due to the potential for slip between the highly loaded spline teeth under cyclic loads. The work reported here aims to demonstrate the feasibility and difficulties of applying a finite element based fretting wear simulation tool, which incrementally updates the contact geometry with material removal, to this problem. The method calculates the local wear that is the wear at each contact node, as a function of local contact pressure and local slip. It is calibrated using wear coefficient data from round-on-flat tests under representative loading conditions. The method has been previously validated against round-on-flat fretting test results for a range of contact loads. The problems of applying the simulation tool to the complex geometry of a helical spline coupling are discussed. The predictions are compared with results from fatigue tests on a reduced scale aeroengine type spline coupling and a previous approach to wear prediction which did not incorporate the evolving contact geometry.