高速硬切削加工表面白层形成机理研究

发布时间：2019-06-25 13:57

【摘要】：白层是高速硬切削的特有现象,对加工表面完整性和零件的服役性能有着重要影响。针对高速硬切削加工表面白层问题,进行了对GCrl5淬硬轴承钢高速硬切削试验和表面白层测试,研究了不同切削条件下的白层形成机理,分析了切削速度和刀具磨损状态对白层特征的影响规律。分析结果表明,白层厚度随切削速度和后刀面磨损的增大而增大,而其分布的均匀性和连续性也将变差;切削速度和后刀面磨损的增加引起切削温度升高,导致加工表面快速淬火效应,使得白层厚度增大,其中切削速度的影响较为显著;在切削速度较低(100 m/min左右)时白层的形成机理主要为塑性变形,切削速度超过300 m/min则主要是马氏体相变所致,而在中间切削速度(200 m/min左右)时为2种机理的混合作用结果。
[Abstract]:White layer is a unique phenomenon of high speed hard cutting, which has an important influence on the integrity of machining surface and the service performance of parts. Aiming at the problem of white layer of surface machined by high speed hard cutting, the high speed hard cutting test and surface white layer test of GCrl5 hardened bearing steel were carried out. The formation mechanism of white layer under different cutting conditions was studied, and the influence of cutting speed and tool wear state on the characteristics of white layer was analyzed. The analysis results show that the white layer thickness increases with the increase of cutting speed and rear tool surface wear, and the uniformity and continuity of its distribution will become worse, and the increase of cutting speed and rear tool surface wear will lead to the increase of cutting temperature, which leads to the rapid quenching effect of machining surface and the increase of white layer thickness, in which the influence of cutting speed is more significant. When the cutting speed is low (about 100 m/min), the formation mechanism of white layer is mainly plastic deformation, while when the cutting speed is more than 300 m/min, it is mainly caused by maraging transformation, while at the intermediate cutting speed (about 200 m/min), it is the result of mixing of the two mechanisms.
【作者单位】：哈尔滨理工大学机械动力工程学院;
【基金】：国家自然科学基金资助项目(51235003,51475125)
【分类号】：TG506

【共引文献】