KDP无磨粒抛光微机械作用力学模型建立与仿真

Modeling and simulation of micro-mechanical interaction in KDP abrasive-free polishing

无磨粒化学机械抛光是一种柔和的表面处理方法,可以有效去除磷酸二氢钾(KDP)晶体表面的小尺度飞切刀纹。在抛光过程中不使用磨粒,KDP晶体与抛光垫粗糙峰直接接触,两者之间相对运动,在表面接触应力的作用下,抛光垫对KDP晶体表面产生微机械作用,在实现材料去除和改善表面质量方面具有重要的作用。为了深入了解无磨粒化学机械抛光中微机械去除作用,文章通过研究表面接触应力分布和变化规律,对抛光过程中的微机械作用进行定量分析,建立了KDP晶体与抛光垫粗糙峰接触力学的数学模型并开展系统研究。根据Hertz理论对抛光过程中KDP晶体表面接触应力进行了计算与分析,研究了抛光压力、摩擦系数、抛光垫杨氏模量和抛光垫粗糙峰半径等抛光参数对微机械作用的影响规律,获得了不同抛光条件下最大许用抛光压力。结合实验结果,对KDP晶体与抛光垫之间的微机械作用进行了实验验证,进一步揭示了KDP晶体无磨粒化学机械抛光去除机理。

Abrasive free chemical mechanical polishing can effectively remove the flying cutter pattern remaining on the KDP surface after the KDP fly-cutting.During the polishing process,the KDP and the polishing pad asperities rubber together.There is micro-mechanical effect in the process that affects the final polishing effect.In this paper,the mathematical model of KDP and polishing pad asperities was established.According to Hertz theory,the surface contact stress of KDP crystal during polishing was calculated and analyzed.The polishing pressure,friction coefficient,Young′s modulus of polishing pad and asperity radius of polishing pad were studied.The influence of polishing parameters on the micro-mechanical action was obtained,and the maximum allowable polishing pressure was obtained under different polishing conditions.In addition,the mechanical effects between KDP and polishing pad were further analyzed in combination with the experimental results,and the mechanism of chemical mechanical polishing removal of KDP based on microemulsion was further revealed.