Research on Thin Aspheric Surface Machining Using Elastic Deformation Molding Method
YUAN Julong;WU Zhe;Lü Binghai;DENG Qianfa;ZHAO Ping;LIN Wangpiao;National Engineering Research Center for High Efficiency Grinding, Hunan University;Key Laboratory of Special Purpose Equipment and Advanced Processing Technology of Ministry of Education,Zhejiang University of Technology;
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 500mm 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.