The Effect of Si Addition on the Microstructure, Mechanical Properties, and Wear Rate of the Co-Cr-Mo-Based Biomedical Alloys

Biomedical alloys have gained significant attention due to their high strength, good corrosion resistance, and biocompatibility. These alloys are widely used in orthopedic, dental, and cardiovascular devices. Co-Cr-Mo-based alloys have been extensively used among these alloys due to their excellent mechanical properties and biocompatibility. Si has been added to the alloy matrix to improve the wear resistance and mechanical properties of Co-Cr-Mo-based biomedical alloys. Si has been reported to enhance metallic biomaterials' mechanical properties and wear resistance. The effect of Si addition on the microstructure, mechanical properties, and wear rate of Co-Cr-Mo-based biomedical alloys is investigated. Si with different percentages (0.5-2.5wt.%) is added to the Co-Cr-Mo-based alloy. The results revealed a significant improvement in hardness and wear resistance. The inclusion of Si resulted in the formation of chromium silicide (Cr3Si) phases, which have a much higher hardness. It contributed significantly to enhancing the hardness and, thus, the wear resistance of these alloys. The results revealed that the wear resistance is enhanced by 73.5% and 40.75% for (2.5wt.%) (2.0wt.%) Si content, respectively. The hardness is improved by 30% when the Si content reaches 2.0% and then reduced as the Si (wt%) increases.