Investigation of Contact and Friction Behavior of Natural Cartilage by Glass Slope Configuration

Based on the irregular surface of natural joint configurations, the contact and friction behaviors of reciprocating sliding between natural cartilage and glass were investigated by the variation of glass gradient angle, preloading time and sliding velocity. Contact displacement, contact load and coefficient of friction from natural cartilage and glass in sliding were measured by the UMT-2 testing machine. Contact displacements were decompounded by the five-point sliding average method to gain cartilage deformation and glass slope. These results showed that cartilage deformation increased nonlinearly with time. Gradient angles played an evident role on the contact state of cartilage friction configuration and functioned as a positive relation with cartilage deformation and coefficient of friction. Preloading time and sliding velocity could enlarge these roles affected by different gradient angles. The instantaneous difference of coefficient of friction reflected dissipation energy state at the endpoint of cartilage friction configuration, and the value of the highest point was always higher than that of lowest point.