碳化硅研抛加工过程中亚表面损伤的研究

Study on subsurface damage in the silicon carbide polishing process

碳化硅抛光加工中极易出现表面/亚表面损伤,使其应用受限。基于研抛加工中脆性材料去除机理,建立亚表面损伤深度(SSD)的理论模型。利用有限元仿真模拟了单颗粒抛光加工的过程,分析了不同研抛参数(抛光速度、抛光深度和磨粒顶角)对SSD的影响。结果表明,当加工深度大于脆性材料临界切削深度时,材料去除主要是脆性模式;SSD随着磨粒顶角以及抛光深度的增大而增大,随着抛光速度的增加而减小,但是抛光速度过高会不利于亚表面损伤的控制。由于抛光过程中运动学特性,抛光速度对SSD的影响大于抛光深度和磨粒顶角。

The application of silicon carbide is often limited due to easily causing surface/subsurface damage in the polishing process. Based on the removal mechanism of brittle material in polishing process,the theoretical model of subsurface damage depth（ SSD） is established. The process of single particle polishing is simulated by finite element simulation,and the influence of different polishing parameters（ polishing speed,polishing depth and abrasive grain angle） on SSD is analyzed. The results indicate that the material removal is mainly brittle mode when the processing depth is bigger than the critical cutting depth of the brittle material; SSD increases with the increasing abrasive grain angle and polishing depth; SSD decreases with the increasing polishing speed,however,the ultra-high polishing speed is not helpful in SSD control. Because of the kinematic characteristics of polishing process,the influence of polishing speed is greater than the polishing depth and abrasive grain angle.