Research On The Key Techniques And Process Optimization Of Magnetorheologcal Finishing And Its Application

With the rapid development of the high technology, the application of optical parts becomes more and more popular in technical fields, i.e. Aeronautics and Astronautics, space exploration, military reconnaissance, laser fusion etc. Meanwhile, the sophistication of the optical parts as well as the quality is highly required. As the traditional manufacturing can no longer meet the modern requirements in aspect of production efficiency as well as in aspect of sophistication, so it is urgent to develop a new type of advanced polishing method with highly efficient and high-quality.Magneto-rheological Finishing Technology(MRF)is a new type of optical processing technology developed in recent years to obtain super-smooth surface, In magnetorheological finishing, magnetically stiffened magneto- rheological fluid flows through a preset converging gap that is formed between workpiece surface and moving rigid wall, to create precise material removal and polishing. Not only the face of optical parts after the polishing can be accurately controlled, but also a higher surface quality and high processing efficiency can be finished. Using MRF, the deterministic processing, the optical components can be finished with the help of computer in high accuracy, low surface roughness and high efficiency simultaneously. This dissertation aims at optical glass polishing and processing technology, a research of magnetorheological finishing technology is carried out. The main content of the research in this thesis are as follows:(1) The material removal model of MRF is established and Dwell time Based on matrix theory is studied. In order to have the removal morphology in the polishing process under control, based on the Preston equation, a magnetorheological finishing of the material removal rate of three-dimensional mathematical model is established. ccording to Mathematical model and the workpiece polishing path, Dwell time matrix algorithm was proposed.(2) Based on magnetorheological finishing device developed by themselves,taking the main factors involved in magnetorheological finishing as targets, studied the magnetorheological finishing experimental program, constraints, process parameters and so on. Based on theoretical and experimental research, explore the law of material removal, apply the velocity of the workpiece relative to the tool and experimental data,deduced material removal function z(y_i) taking the magnetorheological finishingprocess parameters as variables, established the magnetorheological finishing multiple effect modeling. The model has been verified in the engineering experiments, and created basic condition for magnetorheological finishing's precision and controlling stability.(3) Experimental study of the magnetorheological finishing parameters. An experiment is carried out to analyze the effects of main parameters (intensity of magnetic field, Workpiece speed, Polishing wheel rotation speed, Polishing gap) in magnetorheological finishing to the surface roughness and material removal efficiency. Finally, we have acquired the best parameters of the single indicator combinations.(4) A research on optimizing the Processing Parameters for magnetorheological finishing based on the Grey Theory. With the balanced match of the magnetorheological finishing parameters and the analysis of the limited experimental data, the single and multi-objective elements in magnetorheological finishing parameters is optimized, and an optimized magnetorheological finishing parameters combination decision is realized.