二烷基二硫代磷酸锌添加剂对油润滑下填充聚四氟乙烯复合材料摩擦磨损性能的影响

Friction and Wear Behavior of Flame-Sprayed Nylon1010 Coating

利用MM-200型摩擦磨损试验机对比考察了聚四氟乙烯(PTFE)及其铜和镍填充复合材料在干摩擦以及液体石蜡和含商品添加剂二烷基二硫代磷酸锌(ZDDP)的液体石蜡-润滑下同GCr15轴承钢对摩时摩擦磨损性能,采用能量色散X射线显微分析(EDXA)测定了钢环磨损表面S和Zn元素的面分布,进而探讨了ZDDP对液体石蜡减摩抗磨作用的影响.研究表明:液体石蜡及含2%ZDDP的液体石蜡润滑均可大幅度降低摩擦副的摩擦系数,同时可显著降低PTFE-30%Ni复合材料的磨痕宽度,但对PTFE-30%Cu复合材料抗磨性能的影响不大.ZDDP作为添加剂可以有效地提高液体石蜡的抗磨作用,但对其减摩作用几乎无影响;ZDDP作为添加剂在摩擦过程中未发生摩擦化学反应,而是以物理吸附或化学吸附的方式在摩擦副接触表面成膜,从而起到抗磨作用.

Polytetrafluoroethylene (PTFE ) composites filled with copper and nickel participates, respectively, were prepared by means of compression molding and sintering in air. The friction and wear behaviors of the resulting filled PTFE composites sliding against SAE-52100 steel in a block-on-ring contact configuration and under the lubrication of liquid paraffin or liquid paraffin-zinc dialkyldithiophosphate (ZDDP) were investigated on an MM-200 test rig. The distributions of Zn and S on the worn steel surface sliding against PTFE or its composites were determined by means of energy dispersive X-ray analysis. It was found that the PTFE composites showed greatly decreased friction coefficients as they slid against the steel under the lubrication of liquid paraffin and liquid paraffin containing ZDDP as the additive. At the same time, liquid paraffin and liquid paraffin-ZDDP as the lubricants contributed to significantly decrease the wear scar width of the PTFE-30%Ni composite, but they had little effect on the wear scar width of the PTFE-30%Cu composite. Moreover, ZDDP as the additive was beneficial to increasing the wear-resistance of the PTFE composites but had little effect on the friction-reducing ability of the base stock. The antiwear ability of the ZDDP additive was attributed to its physico-chemical adsorption on the contact surface of the frictional pair and the formation of an adsorbed boundary-lubricating layer thereon.