Improving tribocorrosion resistance of a medical grade CoCrMo alloy by the novel HIPIMS nitriding technique

In this work, tribocorrosion performance of the High Power Impulse Magnetron Sputtering (HIPIMS) nitrided (F75) CoCrMo alloys was examined with help sliding wear corrosion experiments carried out in Hank's solution. Results indicate that under Open Circuit Potentials (OCP), both and untreated specimens exhibited near similar Sliding-Wear-Corrosion coefficient (KSWC) values (6.52 × 10−15 3.95 m3N−1m−1 respectively). However, benefits HIPIMS nitriding were evident accelerated (anodic potentials) passivating conditions. KSWC an order magnitude lower (6.41× m3N−1m−1) than (3.4 10−14 m3N−1m−1), indicating surfaces had higher resistance against tribocorrosive mechanisms. This superior attributed to formation a microstructure consisting mainly expanded austenite (ƔN) without detrimental CrN phase, which resulted high hardness sustained corrosion. A rationale for synergy between its relation nitride has been presented.