轴承圈加热切削加工表面质量研究

Research on Surface Quality of Heated Cutting Bearing Rings

针对轴承圈易出现疲劳破坏的问题,提出采用预加热硬态切削加工轴承圈外表面的方法。普通硬态切削和预加热硬态切削试验结果表明,将工件内圈预先加热到160℃进行硬态切削加工,有助于减小加工表面的粗糙度,由于内圈加热减小了轴承圈内外表面的温度差,故加工后的表面残余应力显著减小,其值可达-50MPa,加工得到的表面纹理清晰,形貌光滑、规整,刀具进给运动轨迹清晰;加热切削得到的是均匀的锯齿形切屑,并且切屑形态呈螺旋状,与普通硬态切削相比,加热切削过程较为平稳,说明加热切削可获得良好的表面完整性,且不会引来额外的加工硬化。

In view of hard turning processes of bearings,the processing surface morphology of the outer rings of the bearings was obtained after the ordinary hard cutting and the pre heating hard machining.Experimental results show that heated hard turning will help to reduce the roughness of the machined surface when the inner rings of workpieces are pre heated to160℃,due to the inner rings heatings reduce the temperature difference between inner and outer rings of the bearings,the surface residual stress decreases significantly,its value is up to-50MPa,the processed surface textures are smooth and neat,tracks of tool feed motion are clear;there are no obvious changes in the surface hardnesses of the workpieces obtained separately by heated cutting and ordinary cutting.The heated cutting method obtains a uniform saw tooth shaped chip,and the chip shape is in a spiral shape,which shows that the heated cutting processes of bearing rings are relatively stable.,it is beneficial to the formation of smooth surface,which may be used to improve the performance of the bearing rings.