a School of Mechanical and Electrical Engineering , China University of Mining and Technology , Xuzhou , China.
b School of Materials Science and Engineering , China University of Mining and Technology , Xuzhou , China.
J Biomater Sci Polym Ed. 2018 Apr;29(5):562-581. doi: 10.1080/09205063.2018.1426921. Epub 2018 Jan 17.
The torsional friction behavior of the materials (CoCrMo alloy and ultra-high-molecular-weight polyethylene (UHMWPE)) that are used in artificial knee joint replacement (AKJR) were investigated under dynamic loading. The torsional friction torque, wear loss and scars and stress distribution were analyzed and compared. The results show the following: (1) the friction torque declines rapidly at the beginning of the experiments, and meanwhile, the maximum normal load and the torsional angle amplitude show very little effect on the steady value; (2) the wear loss decreases with the increased torsional angle amplitude but increases with the increased maximum normal load; additionally, as the cycle times increase, the wear rate decreases, and the wear is minimal; (3) unloading and secondary loading significantly reduce the friction and wear of the materials, and thus, patients should rest after prolonged exercise to reduce wear; (4) the margins of UHMWPE and CoCrMo are worn, and the wear mechanism is abrasive wear; (5) around the center of the UHMWPE, the surface is peeled off, and the wear mechanism is fatigue wear; and (6) in terms of the compressive stress and shear stress, the calculated results from a finite element model match the experimental results well.
研究了用于人工膝关节置换（AKJR）的材料（钴铬钼合金和超高分子量聚乙烯（UHMWPE））在动态载荷下的扭转摩擦行为。分析和比较了扭转摩擦扭矩、磨损损失和疤痕以及应力分布。结果表明：（1）实验开始时，摩擦力矩迅速下降，同时，最大法向载荷和扭转角幅值对稳定值影响很小；（2）磨损损失随扭转角幅值的增加而减小，随最大法向载荷的增加而增大；此外，随着循环次数的增加，磨损率降低，磨损最小；（3）卸载和二次加载会显著降低材料的摩擦和磨损，因此，患者应在长时间运动后休息以减少磨损；（4）UHMWPE 和 CoCrMo 的边缘磨损，磨损机制为磨料磨损；（5）在 UHMWPE 的中心周围，表面剥落，磨损机制为疲劳磨损；以及（6）就压缩应力和剪切应力而言，有限元模型的计算结果与实验结果吻合较好。
