辗轧工序对车轮摩擦磨损和接触疲劳性能的影响

Effect of Rolling Process on Wheel Friction and Wear and Contact Fatigue Performances

为研究辗轧工序对车轮使用性能的影响,选择经辗轧工序成形和直接钢水浇筑成形的2种车轮材料,利用GPM-30试验机开展摩擦磨损和接触疲劳性能研究,采用光学显微镜、扫描电子显微镜、ASPEX分析仪、EBSD分析2种车轮材料在不同接触应力状态下摩擦磨损和接触疲劳裂纹萌生扩展行为。结果表明:辗轧工序能够有效地细化车轮材料晶粒,减小珠光体片层间距,从而改善车轮微观组织,减少不均匀塑性变形,抑制裂纹的萌生和扩展,减少磨损量,延长接触疲劳寿命;同时发现夹杂物的形态影响接触疲劳试验亚表面裂纹的萌生。

In order to study the effect of rolling process on wheel friction and wear and contact fatigue performances,two kinds of wheel materials formed by rolling process and direct molten steel casting were selected,and their friction and wear and contact fatigue performances were studied by using GPM-30 testing machine.The friction and contact fatigue crack ini⁃tiation and propagation behavior of the wheel materials under different state of contact stress was analyzed by optical micro⁃scope,scanning electron microscope,ASPEX analyzer,and ZEISS Sigma 500 EBSD.The results show that rolling technology can effectively refine the grain size of wheel material,decrease pearlite regiment and pearlite lamellar spacing,improve the microstructure of wheel,reduce the uneven plastic deformation,inhibit the initiation and propagation of cracks,reduce wear and prolong the contact fatigue life of wheel material.It is found that the subsurface crack initiation in contact fatigue test is closely related to the morphology of inclusions.