Microwave-Sintered Nano-SiC Reinforced 8SiC/Ti-3Cu Composite: Fabrication, Wear Resistance, Antibacterial Function, and Biocompatibility.

Abstract

The significance of biomedical applications of Ti alloys is best emphasized by their widespread utilization as implantable materials, such as internal supports and bone replacements. Ti alloys are sensitive to fretting wear, which leads to the early failure of Ti implants. Improved wear resistance of such implants is essential to ensure a prolonged implant life. Based on the structure-function-integrated concept, this work unprecedentedly designs and fabricates an antibacterial 8SiC/Ti-3Cu composite with improved wear resistance using microwave sintering from pure Ti, Cu, and nano-SiC powders. For comparison, SiC-free Ti-3Cu composite is manufactured under the same conditions using microwave sintering. The addition of 8 vol.% SiC to Ti-3Cu significantly reduces the porosity and pore size of composites. The 8SiC/Ti-3Cu shows a Vickers hardness of 353 HV, compressive strength of 803 MPa, elastic modulus of 28.7 GPa, and a significantly increased wear resistance (wear rate decreased by 70% compared to Ti-3Cu). In addition, 8SiC/Ti-3Cu exhibits excellent electrochemical corrosion resistance, biocompatibility in relation to MC3T3-E1 cells, and a bacteriostatic rate over 99% against E. coli. The combination of the wear-resistant nano-reinforced SiC and antibacterial Ti₂Cu in the 8SiC/Ti-3Cu composite renders it a highly promising implant material.