采用热压固化成型法制得了尺寸范围在9-50μm、密度为0.9413g/cm^3、相对分子量为6×10^6的粉末状超高分子量聚乙烯(UHMWPE)颗粒;并用γ射线平面静止辐照方法,分别用120kGy、250kGy和500kGy剂量辐照样品,辐照剂量率为5kGy/h。采用UMT-Ⅱ多功能摩擦试验机考察了不同辐射剂量下交联UHMWPE的生物摩擦学性能,采用电子扫描电镜(SEM)分析了磨损表面形貌并讨论了其磨损机理。结果表明,辐射剂量为120kGy的UHMWPE磨损率最小,随着辐射剂量的增加,摩擦系数逐渐增大,辐射交联后UHMWPE的摩擦磨损性能均优越于未辐射UHMWPE的摩擦磨损性能。
Specimens are made by hot-pressing solidification method. Ultrahigh molecular weight polyethylene (UHMWPE) particles with size of 9-50μm and density of 0. 9413g/cm^3, and relative molecular weight of 6 × 10^6 are selected. Then using y-ray plane static radicalization, the specimens are irradiated with 120kGy, 250kGy and 500kGy respectively, dosage rate is 5kGy/h. Biotribological property of different irradiation dosage of UHMWPE is investigated using UMT-Ⅱ multi-function wear instrument, the worn surfaces of UHMWPE are examined by scanning electron microscope(SEM), and its wear mechanism is analyzed. It has been found that the specimen with 120kGy dosage has the least wear rate, the coefficient of friction increasingly rises with the dosage increasing, the friction and wear properties of cross linked UHMWPE is superior to untreated UHMWPE.