平面磨削淬硬GCr15轴承钢变质层形成规律实验研究  

Research on the formation rule of surface grinding affected layer of hardened GCr15 steel

作　　者：郭吉恩 GUO Jien(School of Automotive and Mechanical Engineering,Changsha University of Science&Technology,Changsha 410114,CHN)

机构地区：[1]长沙理工大学汽车与机械工程学院,湖南长沙410114

出　　处：《制造技术与机床》2023年第11期137-140,160,共5页Manufacturing Technology & Machine Tool

摘　　要：淬硬轴承钢磨削过程中产生的变质层对零件使用性能有直接影响。为提高轴承零件的加工质量和加工效率,文章开展了平面磨削淬硬GCr15轴承钢变质层形成规律的实验研究,研究了磨削参数对磨削过程中磨削力、磨削温度和变质层厚度的影响,观测了变质层组织,探究了变质层的显微硬度的变化规律。研究结果表明:磨削力和磨削温度随着切深的增大而增大,冷却方式对切向磨削力有显著影响;磨削过程的升温速率高达104℃/s,降温速率也达到103℃/s;温度是影响变质层形成的主要因素,暗层厚度随着温度升高而增大,高温是白层形成的必要条件,磨削温度超过名义相变温度(745℃)后白层厚度出现突增,暗层与白层的厚度之比大于4;白层硬度高于基体,表层硬度随着切深的增大而增大,最高硬度达到1057HV,而暗层发生了软化,最低硬度仅为492HV。The affected layer generated during the grinding process of hardened bearing steel has a direct impact on the performance of the parts,in order to improve the processing quality and efficiency of bearing parts,this paper conducted an experimental study on the formation law of affected layers in surface grinding hardened GCr15 bearing steel,the effects of grinding parameters on grinding force,grinding temperature,and affected layer thickness during the grinding process were studied,and the microstructure of the affected layer was observed.the variation law of microhardness of the affected layer was explored.Research has shown that the grinding force and grinding temperature increase with the increase of cutting depth,and the cooling method has a significant impact on the tangential grinding force;the heating rate during the grinding process is as high as 104℃/s,and the cooling rate is also up to 103℃/s;temperature is the main factor affecting the formation of the affected layer,and the thickness of the dark layer increases with increasing temperature,high temperature is a necessary condition for the formation of the white layer,after the grinding temperature exceeds the nominal phase transition temperature(745℃),the thickness of the white layer suddenly increases,and the ratio of the thickness of the dark layer to the white layer is greater than 4;the hardness of the white layer is higher than that of the substrate,and the surface hardness increases with increasing cutting depth,reaching a maximum hardness of 1057 HV,while the dark layer softens,with a minimum hardness of only 492 HV.

关 键 词：GCR15轴承钢 磨削 变质层 磨削力 磨削温度 显微硬度 

分 类 号：TG580[金属学及工艺—金属切削加工及机床]