Gamma辐照及加速老化对PE-UHMW/GO纳米复合材料干摩擦磨损性能的影响

采用超声分散,球磨混合和热压成型制备超高分子量聚乙烯(PE-UHMW)/氧化石墨烯(GO)纳米复合材料,并对其进行Gamma辐照和加速老化处理。采用万能材料试验机测试复合材料的压缩强度,采用摩擦磨损试验机测试复合材料的干摩擦磨损性能。结果表明,辐照的PE-UHMW/GO的压缩强度比未辐照的PE-UHMW/GO增加6.109%,辐照+加速老化的PE-UHMW/GO的压缩强度比辐照的PE-UHMW/GO下降14.747%。GO和辐照增加了PE-UHMW的平均摩擦系数,辐照+加速老化的PE-UHMW/GO的平均摩擦系数最大,其值为0.168。添加GO和辐照降低了PE-UHMW的平均磨损率,辐照的PE-UHMW/GO的平均磨损率最低,为1.666×10-4mm3/(N·m);辐照+加速老化增加了PE-UHMW的平均磨损率,GO能抑制PE-UHMW磨损性能降低。辐照与辐照+加速老化的PE-UHMW/GO的磨损形式主要是疲劳磨损,而辐照+加速老化的PE-UHMW的磨损形式主要为磨粒磨损。

Influences of Gamma Irradiation and Accelerated Aging on Drying Friction and Wear Properties of PE-UHMW/GO Nanocomposites

Ultrahigh molecular weight polyethylene (PE-UHMW)/graphene oxide (GO) nanocomposite was prepared by ultrasonic dispersion,ball-milling mixing and hot-pressing molding. PE-UHMW/GO was irradiated by Gamma ray in vacumm and its aging was accelerated in air. The compressive strengths of PE-UHMW/GO were studied by universal material testing machine. The drying friction and wear properties of the nanocomposite were investigated. The experimental results show the compressive strength of irradiated PE-UHMW/GO increases by 6.109% compared with unirradiated PE-UHMW/GO,and the compressive strength of irradiated +accelerated aged PE-UHMW/GO decreases by 14.747% compared with irradiated PE-UHMW/GO. GO and irradiation increase the average friction coefficient of PE-UHMW,and the average friction coefficient of irradiation+accelerated aged PEUHMW/ GO is the largest and its value is 0.168. GO and irradiation reduce the average wear rate of PE-UHMW,and the average wear rate of irradiated PE-UHMW/GO is the lowest,which is 1.666×10^-4 mm3/(N · m). Irradiation+accelerated aging increase the average wear rate of PE-UHMW. But GO can inhibit the reduction of PE-UHMW wear performance. The wear form of irradiated PE-UHMW/GO and irradiated+accelerated aged PE-UHMW/GO is mainly fatigue wear,while the wear form of irradiated +accelerated aged PE-UHMW is mainly abrasive wear.