淬硬轴承钢高速切削过程的实验与仿真

Experiment and Simulation of High Speed Turning Process for Hardened Steel

通过切削实验和有限元仿真相结合。研究了3种典型刃口形式即锋利切削刃口、倒圆刃口和倒棱刃口对高速切削高硬度（60～62HRC）的GCr15材料时的切削温度、切削力和已加工表面残余应力的影响规律。结果显示，在硬态切削条件下，倒棱形式刃口产生的切削热传给刀具和已加工表面的比例较少。对已加工表面残余应力的仿真结果表明，倒棱刃口与倒圆刃口都在已加工表面表层存在拉应力，在距表层150～200μm之间存在一最大的压应力，数值都是-200MPa左右，所不同的是倒圆刃口形式的残余应力变质层的厚度要大一些，与实验数据相比，残余应力的变化规律相同，应力变质层厚度相同，但实验得到的最大压应力数值要大一倍左右。

Through combining the turning experiments with FE simulations, this paper studied the influence rules of force, temperature and residual stress of machined surface on high speed hard turning of bearing steel GCr15 that is hardened to 60- 62 HRC with three kinds of ordinary edge preparations （sharp- edge, hone and chamfer）. The results indicated that the diathermanous proportion of the chamfered edge preparation to the tool and the machined surface is less. The simulation results of the machined surface residual stress showed that the residual tensile stress existed in the machined surface using both honed and chamfered tools, and the highest compressive stress （about- 200MPa） existed among 150 -200μm of the depth into the workpiece surface. The difference was that the depth of the superficial harden layer with honed tools is larger than that with chamfered tools. The change rules of the residual stress and the depth of the surface harden layer are the same as the experimental data, but the highest compressive stress experiment value is two times larger than FE simulations.