微晶玻璃多磨粒交互作用表面形成机理的研究

The glass-ceramic optical components with complex surface have the performances of excellent heat, mechanical,optical,chemical properties as well as high laser damage threshold and zero-expansion. Consequently it have broad prospect of application in the national momentous projects and civil fields. Base on the multi-particles interactions, the behaviors such as brittle-ductile transition, material Removal, the thermal transmission and the abrasive wear in the nano-grinding of the glass-ceramic with complex surface are researched in this project,, and the nano-scaled removal mechanism of multi-grains is revealed. a generating mechanism of the glass-ceramic optical devices with complex surface is elucidated. On these bases, a novel nano-grinding method based on a dynamic balance removal in multiple coupled fields is proposed. Specifically, a dynamic equilibrium between the interfacial chemical effect and the mechanical removal of abrasive is established by promoting reactions (the abrasive and workpiece, the bond and workpiece, the grinding fluid and workpiece) initiatively. Therefore, the surface damage and subsurface damage caused by brittle remove can be eliminated. Finally, by processing experiment of typical glass-ceramic optical devices with complex surface, the processing mechanism and technique are further improved, and the glass-ceramic optical devices of ultra-precision and high quality can be obtained. This project will expand the application fields of the glass-ceramic materials and promote the development of manufacturing technology of the optical devices with complex surface.

微晶玻璃复杂型面光学器件具有优良的热、力、光、化学性能以及高的激光损伤阈值和零膨胀性能，在国家重大工程及民用领域有着广泛的应用前景。本项目基于多磨粒交互作用机制针对光学功能微晶玻璃复杂型面纳米磨削过程中材料演变、材料去除、磨粒摩擦磨损等行为进行研究，揭示多磨粒交互作用机制下纳米尺度的材料去除机理，阐明光学功能微晶玻璃复杂型面创成机制；开发光功能微晶玻璃化学-机械动态平衡去除的新型纳米磨削方法及工艺，通过主动增强纳米磨削过程中的界面化学效应，使其与磨粒的机械去除作用达到动态平衡，从而消除因发生脆性去除而造成的表面及近表面损伤；并通过典型微晶玻璃复杂型面光学器件实验加工，完善加工机理及工艺研究，实现微晶玻璃复杂型面光学器件超精密高质量加工。本项目的研究将拓展光学功能微晶玻璃材料的应用领域，促进复杂型面光学元器件制造技术的发展。

本项目对微晶玻璃器件的纳米加工机理开展了研究，提出了基于多磨粒交互动态作用机制的磨削过程中材料去除分析方法，利用FIB加工技术实现了自主设计的多磨粒刀具（压头）的加工制造，结合超精密加工机床搭建了多磨粒压/划削实验系统，基于多磨粒交互动态去除作用机制建立纳米尺度下微晶玻璃材料的去除模型，并对加工过程中脆塑转化，表面完整性、复杂型面创成机制等行为进行了研究。实验结果表明，磨削中三种裂纹相互作用导致的材料去除：相邻划痕之间亚表面横向裂纹之间的相互作用；相邻划痕之间表面径向裂纹之间的相互作用；划痕亚表面横向裂纹与表面径向裂纹的相互作用。研究了微晶玻璃加工过程中多场耦合作用机理，对于磨削过程中的多磨粒作用形成的力学场及其耦合作用进行了建模和实验分析，确定了磨削过程中应力场和速度场变化对于微晶玻璃材料特性的影响，阐明了速度效应对于磨削过程中材料去除机理的影响机制。在此基础上。通过主动干预微晶玻璃和磨削液间的化学反应，更容易实现延性材料去除。在机理研究基础上进行了微晶玻璃复杂型面创成机制及方法的研究，分别对于实现非球面阵列微晶玻璃器件所需的砂轮轨迹规划、砂轮修整方法及工艺、砂轮形状检测、误差分析及补偿等技术开展了研究，实现了微晶玻璃非球面及非球面阵列器件的加工。