基于光滑粒子流体动力学法单颗磨粒超声辅助磨削陶瓷材料的磨削力仿真研究

为了揭示轴向超声振动对磨削Si C陶瓷、Al2O3陶瓷的磨削力影响机制,利用光滑粒子流体动力学(SPH)法对单颗金刚石磨粒磨削Si C陶瓷、Al2O3陶瓷的磨削力进行仿真,提出在单颗磨粒模拟磨削中应将平均未变形切屑厚度作为磨削深度。通过分析轴向超声振动振幅与磨粒速度对平均未变形切屑厚度的影响,发现平均未变形切屑厚度随着超声振动振幅的增加而减小、随着磨粒速度的降低而减小。仿真结果表明:与普通磨削(CG)相比,轴向超声振动能够有效降低磨削力;随着超声振动振幅的增加磨削力降低比率增大;在相同磨削参数下,磨粒切削Si C陶瓷时磨削力大于切削Al2O3陶瓷的磨削力。

A Simulation Investigation on Grinding Forces in Ultrasonic Assisted Grinding of Ceramics with Single Abrasive Grain by Using SPH Method

In order to investigate the influence of axial ultrasonic vibration on the grinding force during ultrasonic assisted grinding (UAG) of SiC and Al₂O₃ ceramics, the grinding forces of UAG SiC and Al₂O₃ ceramics with single diamond abrasive grain are simulated by using smoothed particle hydrodynamic (SPH) method. In the simulation，the average undeformed chip thickness is set as the depth of cut. It is found that the average undeformed chip thickness decreases with the increase in ultrasonic amplitude and the decrease in abrasive velocity. The simulation results of grinding forces show that the assistance of axial ultrasonic vibration can effectively reduce the grinding forces，and the higher ultrasonic amplitude has a positive effect on the decrease in grinding forces compared with that during conventional grinding. Under the same grinding parameters，the grinding forces in the grinding of SiC ceramics are larger than those in the grinding of Al₂O₃ ceramics.