基于控制研磨深度的金刚石研磨质量分析

Diamond grinding quality analysis based on controlled grinding depth

为了探究金刚石器件在机械研磨过程中原子层面的材料表面成形和亚表面损伤机制,利用分子动力学(molecular dynamics,MD)方法建立金刚石多磨粒研磨金刚石工件的模型,仿真研究金刚石材料表面成形的过程,并对比不同研磨深度对研磨力、材料回弹率和材料亚表面损伤的影响规律。分析表明:堆积在磨粒之间的切屑原子具有微研磨的作用,磨粒之间的相变区在研磨的作用下逐渐融合在一起,形成金刚石材料的加工表面;分别以h=0.36 nm、0.71 nm、1.07 nm、1.43 nm的研磨深度进行研磨,研磨深度超过0.71 nm后才能有效抑制金刚石晶体材料回弹,但增大研磨深度会增加金刚石工件表面堆积原子,不能改善其表面研磨质量;研磨深度在0.71 nm范围内的金刚石亚表层损伤较小且稳定,超过0.71 nm的研磨深度会使损伤快速增大,且会出现超过3.00 nm的大纵深损伤。

In order to explore the surface grinding quality and subsurface damage law of the grinding depth on the diamond material,the model of diamond workpiece ground by multi grits is established by molecular dynamics(MD)method.The effect of different grinding depths on the grinding force,the grinding quality of the surface and the subsurface damage characteristics of the material is studied.The analysis shows that the chip atoms accumulated between the grits have the effect of micro-grinding,and that the amorphous area between the grits is gradually fused together under the action of grinding to form the processing surface of the diamond material.The grinding depths of h=0.36 nm,0.71 nm,1.07 nm and 1.43 nm are used respectively.The springback of diamond crystal material can be effectively inhibited only when the grinding depth exceeds 0.71 nm.However,increasing the grinding depth will increase the accumulation of atoms on the surface of diamond workpiece,which cannot improve the grinding quality.At the same time,the increase of the grinding depth will intensify the subsurface damage to the diamond workpiece.The subsurface damage of the material with a grinding depth below 0.71 nm is small and stable.However,the damage increases rapidly when the grinding depth exceeds 0.71 nm and large-depth damage over 3 nm appears on the subsurface.