硬度匹配对轮轨滚动接触疲劳损伤行为的影响规律研究  

Study on the Influence of Hardness Matching on Rolling Contact Fatigue Damage ofWheel-Rail Materials

作　　者：贾劭飞 李英奇 周韶博 刘佳朋 王泓豪 丁昊昊[1] 刘启跃[1] 王文健[1] JIA Shaofei;LI Yingqi;ZHOU Shaobo;LIU Jiapeng;WANG Honghao;DING Haohao;LIU Qiyue;WANG Wenjian(Tribology Research Institute,State Key Laboratory of Rail Transit Vehicle System,Southwest Jiaotong University,Chengdu 610031,China;Metals&Chemistry Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]西南交通大学轨道交通运载系统全国重点实验室摩擦学研究所,成都610031 [2]中国铁道科学研究院集团有限公司金属及化学研究所,北京100081

出　　处：《材料导报》2024年第S01期415-421,共7页Materials Reports

基　　金：国家自然科学基金区域创新发展联合基金(U21A20167);2024年度西南交通大学优秀青年团队培育项目;中国铁道科学研究院集团有限公司院基金课题(2021YJ230)。

摘　　要：随着我国铁路的高速发展,轮轨在服役过程中的疲劳损伤问题愈加突出,因此,本工作利用MJP-30A滚动磨损与接触疲劳试验机研究轮轨滑差率、轮轨硬度比对滚动接触疲劳裂纹发展的影响。结果表明:滑差率较小时,疲劳裂纹较短,且裂纹沿着表面小角度扩展;滑差率大时,切向力增大,表层裂纹会被磨掉。循环转数小时,裂纹均停留在试样表层,扩展不明显;循环转数过大时,枝裂纹扩展相互连接形成网状。对比不同硬度材料的裂纹扩展试验发现:不同硬度匹配对裂纹扩展有着较大影响,硬度高的材料表面塑性变形较小,裂纹扩展速度慢,裂纹长度、宽度以及深度都较小;硬度低的材料裂纹扩展速度快,裂纹长度、宽度以及深度都有所增加。裂纹在试样中不同深度处的扩展速度有着较大差异,在靠近试样表面的裂纹需要克服的扩展阻力较大,故大多裂纹都停留在塑性变形层区域;一旦裂纹突破至基体区域,裂纹的扩展速度就会急剧增加。With the rapid development of heavy-haul railway in China,the fatigue damage problem of wheel-rail during service has become increasingly prominent.Therefore,this work used the MJP-30A rolling wear and contact fatigue tester to study the influence of wheel-rail slip ratio and wheel-rail hardness ratio on the initiation and development of rolling contact fatigue cracks.The results show that when the slip ratio is small,the fatigue cracks are short and the cracks expand along the surface at a small angle;when the slip ratio is large,the tangential force increases,and the surface cracks are worn away.After hours of cyclic rotation,the cracks remain at the surface of the sample and the expansion is not obvious;when the cycle number is too large,branch cracks expand and connect to form a network.Comparing the crack expansion tests of different hardness materials,it is found that different hardness matching has a significant impact on crack expansion.Materials with high hardness have less plastic deformation on the surface,slow crack propagation rate,and small crack length,width,and depth;materials with soft hardness have fast crack propagation rate,and the crack length,width,and depth increase.The propagation speed of cracks at different depths in the sample varies greatly.Cracks near the surface of the sample require greater resistance to propagation,so most cracks remain in the plastic deformation layer region.Once the crack penetrates into the matrix region,the propagation speed of the crack increases dramatically.

关 键 词：疲劳裂纹 硬度匹配 滑差 塑性变形 微观组织 

分 类 号：TH117.1[机械工程—机械设计及理论]