中文摘要：

磁流变抛光技术是实现KDP晶体超精密加工的新方法，但磁流变液中的铁粉容易嵌入质软的KDP晶体表面。本文提出了利用基于低能离子溅射原理的离子束抛光技术去除KDP表面嵌入的铁粉。利用红外拉曼光谱和白光干涉仪分别分析了低能离子束抛光前后KDP晶体表面物质结构变化和表面粗糙度的变化；结果显示，低能离子束溅射不改变KDP晶体表面的组成结构，并改善了KDP晶体表面质量，因此离子束抛光可用于KDP晶体的加工；利用飞行时间二次离子质谱分析技术分别对单点金刚石车削、磁流变抛光和低能离子束抛光后的KDP晶体表面进行元素分析，结果显示低能离子束抛光可有效去除磁流变抛光在KDP晶体表面嵌入的铁粉。

英文摘要：

Magnetorheological figuring （MRF） is one of the ultra-precise machining methods for KDP crystal, but iron powders from magnetorheological fluid are easy embedding into the soft KDP crystal. In order to remove these iron powders, ion beam figuring （IBF） based on low energy ion sputtering was put forward to bombard KDP surface polished by MRF. The changes of crystal structures and surface roughness of KDP before and after IBF were analyzed by Raman spectral analysis technology and white light interferometer, respectively. Moreover, surface elements of KDP crystal machined by MRF, IBF were researched through secondary ion mass spectroscopy （SIMS） analysis. The results indicated that crystal structure is not changed and the roughness is improved by low energy ion sputtering, which means that IBF could be used for machining KDP crystal. After IBF the iron powders on the surface of KDP crystal are cleaned on the whole.