超高分子量聚乙烯/Al_2O_3生物摩擦学特性的研究

在自制销 -盘摩擦磨损试验机上评价了超高分子量聚乙烯 (UHMWPE)与 Al2 O3陶瓷摩擦副在干摩擦和生理盐水、蒸馏水及人血浆润滑条件下的摩擦学特性 ,用扫描电镜观察试样磨损表面形貌并分析磨损机理 .结果表明 :在干摩擦和生理盐水及蒸馏水润滑条件下的起始摩擦系数较接近 ,血浆润滑条件下的起始摩擦系数最低 ;稳态摩擦系数在干摩擦时最大 ,蒸馏水润滑条件下最小 ,生理盐水和人血浆润滑条件下较接近并比蒸馏水润滑下的高 ;干摩擦下UHMWPE的磨损率最大 ,血浆润滑条件下的最小 .干摩擦下 UHMWPE磨损表面可见大量不规则的细小纤维状磨屑 ,蒸馏水润滑下 UHMWPE磨损表面可见明显的塑性变形和疲劳剥落迹象 ,而血浆润滑条件下 UHMWPE磨损表面则可见大量的疲劳微裂纹

Investigation of the Bio-tribological Properties of UHMWPE-Al_2O_3 Ceramic Pair under Dry Sliding and Lubricated Conditions

The tribological properties of UHMWPE rubbing against Al 2O 3 ceramic under dry sliding and lubrication of fresh plasma, distilled water and physiological saline were investigated on a pin on disc friction and wear tester made in our laboratory. The worn surfaces of UHMWPE pin and Al 2O 3 ceramic disc were examined with a scanning electron microscope (SEM). It has been found that the initial friction coefficients under dry sliding and lubrication of saline and distilled water are similar, that under plasma lubrication is the lowest. The highest steady state friction coefficient is recorded under dry sliding and the lowest one registered under lubrication of distilled water, while almost the same friction coefficients in between are obtained under lubrication of plasma and saline. The highest wear rate of UHMWPE is observed under dry sliding while the lowest one recorded under lubrication of plasma. Moreover, different wear mechanisms have been observed for UHMWPE pin under dry sliding and various lubricating conditions, which is related to its different tribological properties therewith.