The Global Modification Method And Device For Planar Components Based On Pattern Polishing Pad

High-precision planar components are an important part of precision mechanical and optical devices.Research on high-precision planar processing technology is of great significance in improving the manufacturing level of precision devices.The application in the demand for high-precision planar components requires the accuracy of the surface of the planar components(such as the accuracy of the surface profile),and the continuous improvement of processing efficiency.The material removal rate of the workpiece surface in conventional polishing is not controllable,resulting in low processing efficiency.In this paper,relevant researches on polishing technology both at domestic and abroad have been conducted.Improvements have been proposed for the conventiaonal processing methods to solve the problem of controllability of the overall material removal rate,and global profile polishing of the planar components has been proposed.The global profile polishing is based on the initial surface profile of the planar component and the purposeful control of the overall material removal rate distribution on the surface of the component to achieve the overall profile of the planar component.In order to achieve high efficiency and controllable modification,this paper studies the global profile polishing method for high-precision planar components.The main research work of this paper is as follows:(1)Based on the theoretical study of Preston equation,the motion of the polished workpiece was analyzed,and the global modification method was used to predict the material removal rate on the workpiece surface.The radial material removal rate distribution of the workpiece was changed by the contact state between the workpiece and the pattern polishing pad.The design process of the ring groove of the polishing pad was deduced,and the surface profile prediction of the workpiece and the strategy for optimizing the processing time were obtained.Through the establishment of a global modification process,a dedicated global modification device was built.(2)The effect of the pattern polishing pad structure on the material removal rate distribution was analyzed,by using a global modification device to process the K9 plane optical glass.Through the polishing of multiple workpieces,the stability of the workpiece material removal rate was analyzed.By studying two types of polishing pad materials(PVC polishing pad and polyurethane polishing pad)and using ring grooves with different groove position parameters,the effect of ring groove structure on the prediction of workpiece material removal rate was analyzed,and the experiment and theory results of the workpiece material removal were analyzed.The difference is obtained by controlling the variable factors of polishing.(3)Applying the global modification polishing method,theoretically optimized design and reasonable process parameters obtained were used to modify the profile of K9 optical elements with different profiles,and the feasibility of modification was verified.The workpiece surface profile with the PV value of 0.406 μm was obtained by modifying the workpiece surface profile with thePV value of 1.804 μm.Through the original surface profile with the PV value of 0.756 μm,using a round of modification processing,the workpiece surface profile with the PV value of 0.276 μm was obtained.Through experiments,it is necessary to combine the prediction method with reasonable process parameters for elements with different surface values.