基于磁性离子液体[bmim]FeCl4的完全无颗粒型磁控抛光KDP新机理研究

Potassium Dihydrogen Phosphate (KDP) is a kind of excellent non-linear optic crystal, which has significant application prospect on accelerating the development of clean nuclear energy and advanced weapons. But it is considered to be one of the most difficult optical materials to process due to its anisotropy, low hardness, high brittleness, high deliquescence and extreme sensitivity to temperature changes, so its finishing with ultra-smooth, free of sub-surface defect and impurity faces new challenge. This project is based on the requirement of KDP ultra-precision processing to explore the new principle and new technology of completely non-particle finishing with magnetic ion liquid under the control of external field, the merits of magnetorheological finishing (MRF) is adsorbed and improved according material chemistry acknowledge. It is planned to reveal the creating mechanism of ultra-smooth and non-subsurface defect surface by researching slight mechanical removal with the assistance of magnetic field. The cooperation effect of deliquescence removal and mechanical removal should also be analyzed to construct complex theory to realize exact adjustment with high removal rate. Then, the physical and chemical properties of residue on finishing surface will be characterized for the design of cleaning route. Finally the KDP finishing experiment will be optimized to conclude the processing scheme of high surface quality. This research has important realistic meaning and academic value on development of precise finishing theory and advanced technology.

磷酸二氢钾(KDP)晶体具有优良的非线性光电特性，在清洁核能和高新技术武器领域有着重要的应用前景，但其各向异性、软脆、易潮解、对温度变化敏感等特点使其成为公认难加工光学元件，而超光滑、无亚表面缺陷和无杂质残留的加工要求使其超精密抛光技术面临新的挑战。本项目面向KDP晶体的优质表面需求，吸收磁流变抛光技术优点，将材料、化学知识融入其中并改良，探索基于磁性离子液体的完全无颗粒型磁控抛光新原理与新技术。研究离子液体磁控微机械去除行为，揭示近无亚表面缺陷超光滑表面创成机理；分析微机械去除-水潮解去除协同效应，建立多过程的耦合机制来实现对高去除率抛光的精确可控；研究抛光表面残留离子液体理化特征，提出洁净清洗设计方案；进行KDP抛光综合优化实验，构建超光滑、高去除率、高洁净度表面加工策略。研究成果对发展交叉学科超精密抛光理论以及高新技术具有重要理论意义和应用价值。

研究背景：磷酸二氢钾(KDP)晶体具有优良的非线性光电特性，在清洁核能和高新技术武器领域有着重要的应用前景，但其各向异性、软脆、易潮解、对温度变化敏感等特点使其成为公认难加工光学元件，而超光滑、无亚表面缺陷和无杂质残留的加工要求使其超精密抛光技术面临新的挑战。. 研究内容：本项目面向KDP晶体的优质表面需求，吸收磁流变抛光技术优点，将材料、化学知识融入其中并改良，探索基于磁性离子液体的完全无颗粒型磁控抛光新原理与新技术。研究离子液体磁控微机械去除行为，揭示近无亚表面缺陷超光滑表面创成机理；分析微机械去除-水潮解去除协同效应，建立多过程的耦合机制来实现对高去除率抛光的精确可控；研究抛光表面残留离子液体理化特征，提出洁净清洗设计方案；进行KDP抛光综合优化实验，构建超光滑、高去除率、高洁净度表面加工策略。. 重要结果：在磁流变抛光中引入压应力，通过雷诺方程构造材料机械去除数学模型，仿真分析表明压应力对于去除函数的形态有较明显的影响。水潮解去除耦合机械去除，极大提升去除效率；微量水在线监测与稳定化技术，明显提升去除函数稳定性。基于GIXD原理，证实抛光能有效减缓亚表面变质层。. 关键数据：KDP抛光后粗糙度由2.3nm收敛到0.95nm，飞切刀纹主峰基本去除，迭代抛光两次后，面形精度收敛82%。根据极性相似相溶原理，借助外场声波辅助作用，能够有效清洗KDP表面残留离子液体，且面形精度保持良好。. 科学意义：通过本项目研究，凝聚材料、化学、机械、光学等交叉学科知识，以工程应用为背景，提炼出相关基础科学问题，为 KDP 优质表面加工提供一种新的理论依据和技术支撑，促进相关大科学工程的实施，并推动抛光新原理、新技术的拓展。研究成果对发展交叉学科超精密抛光理论以及高新技术具有重要理论意义和应用价值。