SiO_2/CuO复合纳米粒子添加剂的摩擦学和自修复性能研究

采用化学方法制备了SiO2/CuO复合纳米粒子,分别采用四球摩擦磨损试验机和环-块摩擦磨损试验机考察了其作为矿物油添加剂的抗磨减摩性能及对磨损表面的修复作用。用PHI-5702型多功能X-射线光电子能谱仪表征钢球磨斑所存在的元素及其价态;用Quant200型扫描电子显微镜(SEM)和GENESIS型X-射线能谱仪(EDX)观察分析试块磨痕形貌和元素组成。并探讨了复合纳米粒子添加剂的润滑作用机理。结果表明,复合纳米微粒添加剂在摩擦过程中由于压应力的作用而沉积于磨损表面微观缺陷区域,从而对磨损表面起到良好的修复作用。另外,SiO2/CuO复合纳米微粒添加剂可在摩擦副接触表面吸附、沉积,并在接触区的高温高压下熔融铺展,形成低剪切强度的表面膜,从而减轻摩擦界面的粘着磨损,表现出良好的减摩抗磨性能。

THE STUDY ON TRIBOLOGICAL PROPERTIES AND SELF-HEALING ACTION OF SiO_2/CuO COMPLEX NANOPARTICLES AS AN ADDITIVE IN MINERAL OIL

SiO_2/CuO complex nanoparticles were prepared with a chemical method.Its tribological properties and self-healing action to worn steel surface as an additive in HVI500 oil were evaluated by using four-ball tester and ring-on-block test rig respectively.The morphologies and elemental distributions of the worn steel and four-ball surfaces were characterized by means of scanning electron microscopy(SEM),energy dispersive X-ray analysis(EDX) and X-ray photoelectron spectroscopy(XPS).And the lubrication mechanism of complex nanoparticles as additive was discussed.It was found that the complex nanoparticles as the additive could improve the antiwear ability and load-carrying capacity of the base oil,but they had little effect on the friction-reducing ability of the base stock at a relatively small volume fraction.Moreover,the complex nanoparticles were capable of self-healing the worn steel surface at proper test conditions.The improved antiwear ability and load-carrying capacity of the base stock and the self-healing action to the worn steel surface in the presence of the complex nanoparticles as the additive were attributed to the adsorption and deposition of the nanoparticles on the sliding surface and subsequent formation of a boundary lubricating layer with a small shearing strength.