Wang A, Stark C, Dumbleton J H
Howmedica Inc., Pfizer Hospital Products Group, Rutherford, New Jersey 07070-2584, USA.
J Biomed Mater Res. 1995 May;29(5):619-26. doi: 10.1002/jbm.820290509.
The mechanisms of wear in ultra-high-molecular-weight polyethylene (UHMWPE) acetabular cups were investigated on both laboratory simulator-tested cups and a clinically retrieved component. Two different levels of wear process were identified: one characterized by the formation and detachment of platelet-like flakes from initial machining marks, and the other by the formation of fine ripple and fibrils by repeated passes of microscopic asperities on the femoral head. Both wear processes could be described by a criterion of critical plastic strain. A theoretical model was developed to account for the generation of the microscopic wear particles based on such a critical strain criterion. Its predictions of the dependence of the UHMWPE wear rate on surface roughness and applied load were in excellent agreement with previously published experimental correlations.
在实验室模拟器测试的髋臼杯和临床回收部件上，研究了超高分子量聚乙烯（UHMWPE）髋臼杯的磨损机制。识别出两种不同程度的磨损过程：一种以从初始加工痕迹形成和脱落片状薄片为特征，另一种以股骨头微观粗糙面反复划过形成细微波纹和原纤维为特征。两种磨损过程都可以用临界塑性应变准则来描述。基于这样的临界应变准则，开发了一个理论模型来解释微观磨损颗粒的产生。其对UHMWPE磨损率与表面粗糙度和施加负荷之间依赖关系的预测，与先前发表的实验相关性结果高度吻合。
