A mild oxidation model valid for discontinuous contacts in sliding wear tests: role of contact frequency

The volumetric wear rate of PVD TiN-coated disks sliding against corundum balls has been investigated as a function of wear track diameter (16–50 mm), sliding speed (0.06–1.41 m/s) and contact frequency (1–16 Hz) in uni-directional ball-on-disk sliding wear tests. The wear rate of the disk material is shown to depend not only on the usual test parameters, namely sliding speed and contact load, but also on the contact frequency. In order to take this last parameter into account, a modification to Quinn’s mild oxidation wear model originally developed for the continuous contact of a pin against a disk, is proposed to account for discontinuous sliding contacts. As a result, a low dispersion in the wear test results is obtained in contrast with disk wear data from pin-on-disk and ball-on-disk tests reported in the literature. By including contact frequency in addition to load and speed, as an independent factor, modeling of the mild oxidation wear of materials in discontinuous sliding contacts has been achieved.