Wear mapping of CoCrMo alloy in simulated bio-tribocorrosion conditions of a hip prosthesis bearing in calf serum solution

Wear maps were developed following a series of micro-abrasion–corrosion testing during idealised hip contact conditions for a CoCrMo alloy in a foetal calf serum solution. The main aim of the study was to characterise wear–corrosion or bio-tribocorrosion regimes of the alloy over a range of applied loads and applied potentials. The transitioning micro-abrasion–corrosion mechanisms, synergisms and wastage behaviours in the presence of additional abrasive particles were identified and mapped. Wear maps in earlier work show the wear–corrosion transitions of CoCrMo alloy in the absence of abrasive particles for similar conditions; the wear maps developed in this work were compared. Mapping the micro-abrasion–corrosion regimes indicated that proteins present in foetal calf serum solution, resulting in development of a graphitic tribo-layer, may play a critical role in enhancing or protecting against tribo-corrosive degradation.