Structure-property relationships in a CoCrMo alloy at micro and nano-scales

This investigation considered the multiscale tribo-mechanical evaluations of CoCrMo (Stellite®21) alloys manufactured via two different processing routes of casting and HIP-consolidation from powder (Hot Isostatic Pressing). These involved hardness, nanoscratch, impact toughness, abrasive wear and sliding wear evaluations using pin-on-disc and ball-on-flat tests. HIPing improved the nanoscratch and ball-on-flat sliding wear performance due to higher hardness and work-hardening rate of the metal matrix. The cast alloy however exhibited superior abrasive wear and self-mated pin-on-disc wear performance. The tribological properties were more strongly influenced by the CoCr matrix, which is demonstrated in nanoscratch analysis.