Damage of the Co-Cr-Mo Femoral Head of a Total Hip Prosthesis and Its Influence on the Wear Mechanism

Co-Cr alloy is one of the most used alloys for artificial hip joints and offers a good combination of mechanical propertics. corrosion resistance and biocompatibility. To increase its resistance to wear are commonly used hard coating thin layers of Co-Cr-Mo. Analyzing a femoral head ofa Co-Cr modular total hip prosthesis coated Co-Cr-Mo, we found peeling coating, abrasion of the substrate and hardening of abrasion traces against subsurface initial hardness. This paper presents an analysis by the Student test of the microhardness peeling a portion of a scratch from a femoral head explant covered with Co-Cr-Mo, and that demonstrate the transformation of wear mechanism from three bodies abrasion in two bodies abrasion.