Abstract
An investigation has been carried out on the mechanisms of wear of the surgical implant alloy "Vinertia", based on cobalt-chromium, and an attempt has been made to interpret the mechanisms in metallurgical terms. The alloy in its present surgical form has been found to have wear mechanisms governed by the allotropic form of its matrix and the carbide precipitate to different extents dependent on the type of wear. The alloy showed an improved coefficient of friction under certain conditions after a simple heat-treatment though the wear resistance was not substantially altered. The wear mechanisms were constant over a vide range of speed, but were modified by relatively high speed. The mechanisms deduced from pin and disc wear test specimens were also found to occur in a hip-joint prosthesis that had been worn in an artificial hip-joint simulator, indicating that hip-joint prosthoses exhibit "in vivo" similar wear mechanisms to those experimentally determined.