Bio-Tribological Properties of Bulk Metallic Glasses Sliding Against Si<sub>3</sub>N<sub>4</sub>

Metallic biomaterials are used as bone plate, dental implant, wire, electrode, and so on. For the purpose of providing the medical services with higher quality, the frictional and wear behavior of Cu47Ti34Zr11Ni8, (Cu47Ti34Zr11Ni8)99Si, Zr41Ti14Cu12.5Ni10Be22.5 and Zr57Nb5Cu15.4Ni12.6Al10 bulk metallic glasses (BMG) against ceramic ( Si3N4) at room temperature under dry sliding and lubrication of fresh plasma, distilled water, and physiological saline conditions were investigated on a pin-on-disc testing machine. Under identical sliding condition, the steady state friction coefficients of BMGs were observed with values ranging from 0.6 to 0.9 under dry sliding, 0.5 to 0.8 under lubrication with distilled water, 0.5 to 0.7 under lubrication with physiological saline, and 0.3 to 0.7 under lubrication with fresh plasma, respectively. Wear rates of BMGs indicated significant difference that the Cu-based metallic glasses exhibited higher wear resistance than that of Zr-based glasses. The surface tracks indicated the existence of viscous flow and the material transfer occurred from BMG rod to the ceramic disc. Since tribological properties are not intrinsic properties, those results demonstrated the influences of the environment and the characteristics of BMGs on the frictional behaviors, and furthermore indicated that BMGs may be one of the promising biomaterials in the future.