SiO2/SnO2复合纳米微粒添加剂的摩擦学性能及其对磨损表面的修复作用研究

采用化学方法制备了SiO2 SnO2 复合纳米微粒，分别采用四球摩擦磨损试验机和环一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．用扫描电子显微镜观察、分析了磨斑表面形貌，并探讨了复合纳米微粒添加剂的润滑作用机理．结果表明，SiO2 SnO2 复合纳米微粒添加剂具有优良的减摩抗磨性能，且对磨损表面具有一定的修复作用．其原因在于，SiO2 SnO2 复合纳米微粒在摩擦表面沉积并在接触区的高温高压作用下熔融铺展，形成低剪切强度的表面膜．

Tribological Properties and Self-Healing Action of SiO2/SnO2 Complex Nanoparticles as an Additive in a Mineral Oil

SiO_2/SnO_2 complex nanoparticles were prepared making use of a chemical method. The tribological properties of the resulting complex nanoparticles as an additive in 500SN oil were evaluated using a four-ball machine, while the self-healing action of the additive to the worn steel surface was examined on a ring-on-block test rig. The morphologies and elemental distributions of the worn steel surfaces were analyzed by means of scanning electron microscopy and energy dispersive X-ray analysis. It was found that the complex nanoparticles as the additive contributed to greatly 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 the subsequent formation of a boundary lubricating layer with a small shearing strength.