Evaluation of the fretting wear damage on crowned splined couplings

Splined couplings are widely used in many industrial fields and one of the most problematic failure mode of these components is fretting wear. Fretting wear appears because of the relative motions between teeth and it is mainly due to angular misalignments. Aim of this paper is to set up a procedure in order to identify the entity of the fretting wear damage in crowned splined couplings in real working conditions. The first Ruiz parameter has been chosen to quantify the wear damage being relatively easy to be obtained from the calculation point of view. Experimental tests have been performed by means of a dedicated test rig to validate the theoretical results, in terms of iso-Ruiz maps. The damage entity has also been quantified by measuring the angular rotation before and after each test. Obtained results confirm that, where the fretting map shows higher values of the Ruiz parameter, the fretting damage becomes more important.