ZDDP润滑下表面纳米化316L不锈钢的摩擦学性能

采用SRV摩擦磨损试验机考察了表面纳米化316L不锈钢在PAO4和ZDDP润滑下的摩擦学性能。采用X射线衍射仪(XRD)和金相显微镜表征纳米化样品的微观组织结构,采用扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)分析摩擦反应膜的微观形貌和化学组成。结果表明,表面纳米化明显提高了316L不锈钢的表面硬度,同时在表面产生了具有储油作用的微坑,在PAO4润滑下,纳米化样品的减摩抗磨性优于未处理样品;在添加ZDDP的PAO4润滑下,在纳米化表面形成了链长较短的磷酸盐膜,膜中Zn和P的含量也高于未处理样品,黏着磨损明显减轻,抗磨性提高幅度更为显著。

Tribological Properties of Surface Nanocrystallized 316L Stainless Steel Under ZDDP Lubrication

The tribological properties of 316L stainless steel processed by ultrasonic surface nanocrystallization were investigated by a SRV tribometer under PAO4 and ZDDP lubrications. The microstructural evolutions of the nanocrystallized sample were characterized by X ray diffraction (XRD) and optical microscope. The morphologies of the wear surfaces and chemical composition of tribofilms were investigated by scanning electron microscopy (SEM) and X ray photoelectron spectroscopy (XPS), respectively. The results showed that ultrasonic surface nanocrystallization treatment could significantly improve the hardness of 316L stainless steel. The micro dimples on the nanocrystallized surface might play a role as lubricant reservoirs, thus the friction reduction and anti wear properties of nanocrystallized sample were much better than those of the original sample under PAO4 lubrication. The wear resistance of the nanocrystallized sample was remarkably improved under PAO4+ZDDP lubrication, which was attributed to the formation of a polyphosphate tribofilm with shorter chain length and the higher contents of Zn and P in the tribofilm on the nanocrystallized surface, thus the adhesive wear was reduced significantly with obvious enhancement of anti wear properties.