微坑分布位置对复合润滑结构缸套摩擦磨损性能的影响规律

摘要

The surface texture was etched at the dead point,middle point and whole position on the surface of cylinder liner specimens by electrical discharge machining (EDM).The solid lubrication MoS2 was filled with the micro dimples by ball milling.The influence of the micro dimple distribution position on the tribological characteristics of the cylinder liner was studied by using a contraposition reciprocating test rig.The wear morphology was tested and analyzed by SEM and EDS.The results show that the cylinder liner with a composite lubrication structure can reduce the friction coefficient;however,not all the wear and anti-scuffing properties can be improved.Only the mico dimples on the dead point of the cylinder liner with the composite lubrication structure shows the good friction reduction,wear resistance and anti-scuffing properties,compared with the untreated cylinder liner.The friction coefficient and the wear loss of the piston ring decrease 4.97％-6.26％ and 58.3％,respectively.The scuffing time is prolonged about 10 times.With sliding,MoS2 in the micro dimplesgradually shifts to the surface of the cylinder liner,thus improving the lubrication performance of the dead point and protecting the friction interface.%采用电火花加工方法在FeNi合金镀铁缸套试样表面的止点、中点、全程位置刻蚀微坑织构,采用球磨法对微坑填充固体润滑剂MoS,以制备复合润滑结构缸套.采用对置往复式摩擦磨损试验机,研究微坑分布位置对复合润滑结构缸套摩擦磨损性能的影响规律.采用SEM和EDS研究配副的磨损形貌.结果表明:复合润滑结构缸套能提高承载性能、降低摩擦因数,但不一定都能提高缸套的磨损性能和抗拉缸性能.唯有微坑分布在止点的复合润滑结构缸套相比未处理缸套,表现出良好的减摩耐磨和抗拉缸性能,摩擦因数降低了4.97％～6.26％,对磨环磨损量减少了58.3％,拉缸时间延长了10倍.随着往复运动的进行,微坑中的MoS2逐渐向缸套表面转移,改善了止点区域的润滑性能,良好保护了摩擦界面.