表面织构对金属-聚甲醛材料摩擦副磨损行为与机理的影响

目的研究表面织构对金属-聚甲醛(POM)摩擦副磨损行为和机理的影响。方法通过光刻-电解的方法加工出带有不同参数凹坑的不锈钢试样与聚甲醛(POM)材料配副,在万能摩擦磨损试验机上进行摩擦磨损实验,以评价其摩擦学性能。利用光学显微镜、三维形貌仪和SEM对磨损后的表面形貌以及磨屑形态进行观察分析。结果凹坑深度为5μm、面积率为10%时,减磨效果最明显,磨损率相比无织构试样下降了36.2%。凹坑深度为10μm时,表面织构的引入起到了增大磨损的效果。结论合适参数的表面织构能够有效减小大面积的材料粘着转移现象,对摩擦副具有良好的减磨效果。不恰当的表面织构参数会在凹坑边缘引发严重的应力集中现象,导致不锈钢试样对软材料微切削作用产生,这也是材料磨损率急剧增大的原因。

Effects of Surface Texture on Wear Behavior and Mechanism of Friction Pair Made of Metal and POM

The work aims to study the effects of surface texture on wear behavior and mechanism of friction pair made of metal and POM. Lithography-electrolytic technology was applied to fabricate pairs of stainless steel specimen and POM with dimples in different parameters. Friction-wear tests were carried out ona MMW-1 friction tester to study tribological properties. Surface morphologyand wear debris morphologyof the worn mating surfaces were observed and analyzedwithan optical micro-scope, 3D surface profiler and SEM.Wear rate of the friction pair was the lowest at the dimple depth of 5μm and area density of 10%, which decreased by 36.2% compared to un-textured pairs. The wear rate was increased by introduction of the surface tex-ture at the dimple depth of 10μm. Surface texture with appropriate parameters can reduce POM transfer and wear effective-ly,while surface texture with improper parameters can cause stress concentration around the edges of dimples, thus resulting in sharp increase of wear rate.