空心玻璃微珠/超高分子量聚乙烯复合材料低速重载工况下的摩擦磨损性能

Friction and wear properties of hollow glass microspheres/ultrahigh molecular weight polyethylene composites under low speed and high normal loads conditions

为提升超高分子量聚乙烯(UHMWPE)材料在低速、重载工况下的摩擦磨损性能,使用经偶联剂表面处理的空心玻璃微珠(HGM)对UHMWPE进行填充改性,通过热压成型工艺制备HGM/UHMWPE复合材料。对HGM/UHMWPE复合材料的硬度、结晶度等进行表征,并对该材料进行干摩擦环境下的重载球盘往复摩擦试验以测定其摩擦磨损性能。结果表明,添加少量HGM可以提高UHMWPE的硬度与结晶度。当摩擦时间较短时,加入HGM会在一定程度上增大UHMWPE的摩擦系数,同时磨损率随复合材料中HGM含量的增加而先降低后升高,当HGM含量为1wt%时,复合材料磨损率最低,在50 N与100 N两种法向载荷的摩擦试验中相比于纯UHMWPE磨损率分别降低44.7%与48.4%。随着摩擦时间的增长,复合材料摩擦系数与磨损率均有不同程度的升高。当摩擦时间达到120 min时,HGM含量为2wt%的复合材料平均摩擦系数最低。此时添加少量HGM的HGM/UHMWPE复合材料在磨损率上与纯UHMWPE磨损率接近。

In order to improve the friction and wear properties or ultrahigh molecular weight polyethylene(UHMWPE)under low speed and high normal loads conditions,composites consisting of hollow glass microspheres(HGM)treated with coupling agent and UHMWPE were prepared by hot pressing.The hardness and the crystallinity of composites were characterized,and the friction and wear properties of composites were measured by balldisk reciprocating friction test in condition of high normal loads and dry friction.As the results,the hardness and the crystallinity of composites with a small amount of HGM added are higher than that of the pure UHMWPE.The friction coefficient of composites in a short time becomes higher to a certain extent as the content of HGM rising,and the wear rate decreases first and then increases.The composite with 1wt%HGM content has the lowest wear rate,the wear rate of which decreases by 44.7%and 48.4%in the friction tests under normal loads of 50 N and 100 N respectively compared with the wear rate of pure UHMWPE.With the increase of friction time,the friction coefficient and wear rate of the composites increase to varying degrees.The composite with 2wt%HGM has the lowest average friction coefficient during 120 min-friction-test,and the wear rates of pure UHMWPE and HGM/UHMWPE composites containing a small amount of HGM are close.