薄型非球面弹性变形面形复制加工技术研究

提出一种新型非球面加工技术——弹性变形面形复制加工技术，该技术综合利用光学玻璃材料的线弹性特性以及面形复制加工机理，将复杂的非球面加工转变为简易的平面加工，适合加工薄型大曲率半径非球面。阐述弹性变形面形复制加工技术的基本机理，随后以直径为40 mm、顶点曲率半径为2 500 mm的抛物面作为目标面形，通过有限元仿真确定使工件与靠模紧密贴合所需的工件最小去除厚度，建立加工过程的材料去除模型，并由此确定加工时间。在所搭建的弹性变形面形复制加工系统上进行加工试验，试验结果证明所建立材料去除模型有效。最终工件加工面形精度为PV 0.62 μm。对加工面形精度影响因素进行分析，并提出改进工件加工面形精度的措施。

Research on Thin Aspheric Surface Machining Using Elastic Deformation Molding Method

A novel aspheric surface machining method, elastic deformation molding method, is proposed. Based on the linear elasticity of optical glass and the optical replication mechanism, the new method can convert complicate aspheric surface machining to simply flat surface machining, which is suitable for the machining of thin aspherical component with large curvature radius. The basic principle of the new method is described. Then taking a paraboloid with a diameter of 40 mm and a curvature radius of 2 500 mm as the target machining profile, the minimum material removal depth of workpiece that ensures the close attachment between workpiece and mold is determined by finite element simulation. The material removal model of the proposed method is established and the machining time is calculated. A machining experiment is then carried out on a built elastic deformation molding machining system, and the validation of established material removal model is verified. A parabolic surface with form accuracy of PV 0.62 μm is obtained. The influencing factors of machining form accuracy are analyzed and measures to improve the machining form accuracy in the future work are put forward.