Tribocorrosion behaviour of non-passivating alloys: case examples and approaches to wear-corrosion synergy determination

摘要

Tribocorrosion behaviour of passivating alloys and coatings, such as stainless steels, titanium alloys and hardmetals (WC-CoCr) has received considerable attention in a range of environments of industrial importance. In such cases, the passive film is typically removed from any areas subjected to wear, i.e., the wear track, enabling their activation with respect to surrounding passive areas that are not exposed to tribological contact. Thus, the material undergoes wear-induced corrosion in the wear track, the contribution of which to material losses may be easily assessed through the measured electrochemical data and Faraday's law, as the increase in corrosion rate of the material as the activation in the wear track is evident. Tribocorrosion studies on alloys that do not experience passivation in the environment of interest are much less frequent and require a different approach to wear-corrosion synergy determination, as a slight increase in the corrosion rate within the wear track does not necessarily yield dramatic changes in the overall electrochemical response of the materials. This research gives insights into the tribocorrosion behaviour of non-passivating alloys (bronzes and low-alloy steels) under conditions of industrial importance and alternative approaches to define the wear-corrosion interactions are considered.