基于水辅助激光裂纹修复的石英玻璃高效超精密磨削技术研究

项目名称： 基于水辅助激光裂纹修复的石英玻璃高效超精密磨削技术研究

项目编号： No.51305237

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 机械、仪表工业

项目作者： 姚鹏

作者单位： 山东大学

项目金额： 26万元

中文摘要： 为提高大口径非球面石英玻璃透镜和反射镜磨削精度、表面质量和加工效率，本项目将研究一种新的石英玻璃超精密复合磨削技术与工艺，即先采用二氧化碳激光修复浸入水中的粗磨和精磨后石英玻璃表面残留的微裂纹，再对材料进行延性域磨削。重点研究水辅助激光裂纹修复的作用机理，建立裂纹修复的理论模型；以修复裂纹、降低残余应力为目标，优化水辅助激光裂纹修复的工艺参数。通过单次和原位重复的单颗磨粒压痕和划擦试验，研究石英玻璃在激光裂纹修复后材料的延性域去除机理，建立延性域临界切削深度模型。建立基于三维表面粗糙度的砂轮磨损动态定量评价模型和评价指标体系，为砂轮磨损的原位监测提供高效的新方法。依据此评价指标体系重构砂轮地貌，通过磨削运动学仿真确定延性域磨削工艺参数，进而实现石英玻璃的高效超精密延性域磨削加工。本项目的研究成果对于促进石英玻璃等硬脆材料高效超精密磨削技术的发展具有重要的理论学术意义和实际应用价值。

中文关键词： 石英玻璃；激光辐照；塑性域磨削；裂纹修复；磨削仿真

英文摘要： To minimize the size of large optical systems, a large number of large aperture aspherical lenses and mirrors made of fused silica with diameter of several hundred millimeters to one meter are needed. It is rapid and cost-effective to achieve high surface quality and profile accuracy by precision grinding processes rather than lapping or polish processes. Hence, a new process，ultra-precision grinding incorporating water assisted laser irradiation of fused silica, is proposed in this research project. The subsurface damage (SSD), micro cracks under the surface, on a ground fused silica that immerged in water will be repaired by laser irradiation with carbon dioxide laser. Then, the fused silica can be ground in ductile mode as the undeformed chip thickness is smaller than the brittle-ductile transition depth of cut. The mechanisms of repairing cracks by water-assisted laser irradiaiton will be revealed by researching the coupling effect of heating and plasma shock wave. A prediction model of laser repaired depth will be built. To repair SSD on a ground fused silica and reduce residual stress introduced by laser irradiation, the process parameters of water-assisted laser irradiation wil be optimized by thermo-mechanical coupled visco-elastoplastic finite element simulation. Single and multi-cycle nanoindentation a

英文关键词： Fused silica；Laser irradiation；Ductile mode grinding；Damage repair；Grinding simulation