精密硬车加工轴承套圈的表面完整性试验研究

针对磨削加工中套圈精密加工存在的不足，进行精密硬车削加工轴承套圈新工艺的开发，通过加工试验分析了精密硬车加工轴承套圈的表面完整性，探究了基准面平面度、刀具磨损量等工艺参数与加工精度的对应关系。基于精密硬车削套圈试样的表面粗糙度、沟道圆度、显微硬度、热损伤、金相组织、残余应力分布、加工效率等方面的研究，得出了精密硬车削可达到磨削加工精度的结论，且金相组织稳定，不易存在热损伤，具有可控的残余应力分布和较高的加工效率，有利于产业化生产高精密轴承。利用磁性卡盘装夹套圈，分析试样基准面平面度对精密硬车削套圈沟道圆度的影响，发现提高基准面平面度可以有效提高加工套圈的沟道圆度；分析了刀具磨损对硬车削套圈加工精度的影响，得出在精密加工阶段刀具磨损量是控制套圈圆度的重要监控工艺参数的结论。

Experimental Research of Surface Integrity for Precision Hard Turning Finished Bearing Rings

In order to avoid the shortcomings appeared in grinding and to explore new processing technology of hard turning finished bearing rings, the surface integrity of hard turning rings was studied by experimental method, and the relationship among the flatness of datum surface, the tool wear of cutting edge and the precision of hard turning was investigated. Based on the researches of surface roughness, roundness of raceway, micro-hardness, heat damage, microstructure, residual stress distribution and processing efficiency of the samples, it is found that the processing accuracy of hard turning is as high as that of grinding, while the micro-structure of hard turning remains stable, heat damage does not generate easily, the residual stress distribution is controllable and the processing efficiency is higher. These results are conducive to the industrialization of high precision bearing production. Furthermore, the influences of flatness of datum surface on the roundness of raceway were analyzed while the ring was clamped by magnetic chuck on hard turning machine tools. The results show that better flatness will produce better roundness of hard turning raceway. At last, the influences of tool wear on the processing accuracy of hard turning were analyzed, which reveals that the tool wear is an important cutting parameter to be controlled strictly in finish stage to get better roundness of raceway.