KDP晶体加工表面的亚表面损伤检测与分析

Damage detection and analysis of machined KDP crystal subsurface

采用截面显微法和择优蚀刻法分别对磷酸二氢钾(KDP)晶体从线切割样品制备到磨削、抛光亚表面损伤进行检测,利用OLYMPUS MX40光学显微镜对表面腐蚀现象与亚表面裂纹形状进行观测,并对裂纹深度进行测量。结果表明,由线切割产生的亚表面损伤裂纹形状以"斜线状"为主,裂纹深度最大值为85.59μm;由#600砂轮磨削产生的亚表面损伤深度最大值为8.55μm。在(001)晶面出现了四方形的分布密度较高的位错腐蚀坑;而在三倍频晶面上出现的是密度较低、形状类似梯形的位错腐蚀坑。该研究为KDP晶体亚表面损伤提供了一种检测与分析手段。

The subsurface damage of Potassium Dihydrogen Phosphate （KDP） crystal machined from line-incision to grinding and polishing was detected using section experiment and step etching experiment. The OLYMPUS MX40 optic microscope was used to observe the surface etching phenomena and the sub-surface micro-crack configurations, and to measure the micro-crack depth. The results show that the subsurface micro-crack configurations induced by line-incision is mainly of ＂bias-figure＂, and the max micro-crack depth is 85.59 μm. While by the #600 grinding wheel the max depth reduces to 8.55μm. The square dislocations etching pits with high density are on （001） crystal surface and the low density etching pits with the figure resembled trapezium are on the tripler surface.This study affords a excellent detection and analysis method for the subsurface damage of KDP crystal machining.