面向复杂型面光学器件的超声空化辅助多喷嘴射流抛光工艺机理研究

High-precision and high-gradient aspheric surface, freeform surface, and large-aspect ratio inner-cavity surface optical elements are widely used in modern optical systems. Unfortunately, traditional polishing methods are unable to meet the requirements of practical applications, and this limitation has seriously restricted the progress of major engineering at the national level. To achieve the highly efficient polishing of complex optical surfaces with high steepness and small curvatures, an ultrasonic cavitation-assisted multi-nozzle jet polishing process is proposed in this project. Although preliminary results have been obtained, some deficiencies in basic theoretical research remain. This project intends to use acoustic theory, fluid dynamics theory, and indentation fracture mechanics theory, in combination with numerical analysis and scientific experimentation, to establish a three-phase gas–solid–liquid coupling dynamic flow field model that can reveal the interaction mechanism between abrasive particles, the polishing fluid, cavitation bubbles, and the workpiece under the synergetic effect of ultrasonic cavitation. A theoretical analytical model of material migration is developed to illustrate the physicochemical behavior and evolution mechanism of the surface and subsurface layers of hard, brittle materials. Finally, a theoretical model of material removal and surface generation is also established to map the relationship between polishing process parameters and surface quality and integrity and realize surface shape control and process optimization of complex surface polishing. The results of this work provide an important scientific basis and technical support for the application of the proposed process to the field of ultra-precision optical surface processing.

高精度高陡度非球面、自由表面和大长径比内腔表面光学元件广泛应用于现代光学系统，传统的抛光手段难以满足实际应用需求，严重制约着国家重大工程的进展。针对高陡度、小曲率复杂型面光学器件高效抛光的技术难题，本项目提出超声空化辅助多喷嘴射流抛光工艺，虽然已取得初步研究成果，但在基础理论研究方面存在不足。本项目拟运用声学理论、流体动力学理论及压痕断裂力学理论，结合数值分析和科学实验方法，建立流场气-固-液三相耦合动力学模型，揭示超声空化协同作用下磨粒、抛光液、空化气泡和工件之间界面作用机制；建立材料迁移理论分析模型，揭示射流冲蚀材料的表层及亚表层物化行为与演变机理；建立材料去除和表面生成理论模型，揭示抛光工艺参数和表面质量及完整性的映射关系，实现复杂型面器件抛光的面形控制与工艺优化，为该工艺在超精密光学曲面加工领域的拓展应用提供重要科学依据与技术支持。

高精度高陡度非球面、自由表面和大长径比内腔表面光学元件广泛应用于现代光学系统，传统的抛光手段难以满足实际应用需求，严重制约着国家重大工程的进展。针对高陡度、小曲率复杂型面光学器件高效抛光的技术难题，开展了抛光工艺优化、材料去除机理、表面生成理论模型等方面研究工作。主要研究成果如下：（1）完成了超声空化辅助多喷嘴射流抛光系统的设计优化，研究了超声空化气泡的动力学行为和多喷嘴阵列结构对流场特性和磨粒冲蚀行为的影响机制，为建立射流抛光材料去除理论模型提供了重要依据。（2）研究了射流抛光过程中磨粒对硬脆材料的冲蚀行为和磨损特性，揭示了磨粒冲击硬脆材料时的脆塑转变机制和材料去除机理，为硬脆材料的高效、无损伤抛光提供科学依据和技术支持。（3）建立了射流抛光的材料去除特性与表面粗糙度预测模型，揭示了抛光面形修正算法和轨迹规划理论对抛光质量的影响机制，为复杂型面器件抛光的面形控制与工艺优化提供了重要技术支撑。.本项目发表发表高水平SCI学术论文6篇，其中中科院top期刊3篇，SCI影响因子总和30.208，单篇最高影响因子6.772；获得天津市技术发明一等奖，机械工业科学技术奖技术发明一等奖；受理国家发明专利5项，授权国家发明专利5项、PCT 国际发明专利1项；参加学术会议6人次，其中专家报告3人次，口头报告3人次；入选天津大学“北洋学者”计划1人，新聘博土生导师1人；指导（含协助指导）研究生10人，其中已毕业研究生4人。