Development Of Magnetorheological Polishing Device With Roller For Optical Compoments And Experimental Study

Ultra-precision machining technology is the support technology of optoelectronic device manufacturing with applying aerospace,electronic communication,bioengineering,information technology and other fields,and has made remarkable development,has become an important research content of high competitive enterprises.Magnetorheological polishing(MRP)technology is one of the most effective forms of high surface quality and high shape precision in precision machining technology.It is also the best process to further improve the surface quality after ultra-precision cutting and mirror grinding.Magnetorheological fluid is a new material;it is a common fluid with no magnetic field.With a certain strength magnetic field,magnetorheological fluid will become a viscoplastic"Bingham" medium quickly,and after the magnetic field disappears,magnetorheological fluid can be changed back to the flowing liquid.Magnetorheological fluid has the characteristics of high yield stress,easy redispersibility,fast response time and wide working temperature range.It is an ideal material for developing a new generation device of controlled polishing.According to the above characteristics of magnetorheological fluids,it can be applied to instruments and equipment that need to be controlled by magnetic field,such as magnetorheological damper,brake and polishing device.There are a lot of researches on MRP at home and abroad,but some problems still need to be solved.Therefore,the study of MRP still has important significance.In this paper,the following research is carried out on the MRP device.The main research of this paper includes:(1)The characteristics and use of magnetorheological fluid are introduced by reading a lot of literature.The research status of magnetorheological polishing at home and abroad is expounded,and the research significance of the subject is established.(2)The composition and performance of MRP fluid are introduced,and MRP with roller is raised and its principle is introduced.Based on the "Preston" equation,the mathematic model of MRP was introduced.The plan of the MRP test bed with roller was raised,and each component in the device was designed.By selecting the standard parts of the test bed and the processing non-standard parts,the MRP test bed with roller was assembled in the finally.(3)The magnetic field in the polishing device was analyzed,and different magnetic field schemes were proposed.Finally,one of the magnetic field schemes was selected by analyzing the results.The transmission mechanism determined the power transmission of the polishing device during operation,and a statical analysis and contact analysis of the worm gear in the transmission mechanism were carried out.The results of the analysis met the requirements,thus ensuring the safety and stability of the device during operation.(4)The MRP fluid was prepared independently and the K9 glass was polished with the designed test bed.During the experiment,a variety of parameters were changed and the optimal parameters were selected to test.The surface morphology before and after polishing could be compared,and the surface quality of K9 glass had been greatly improved,the device which was designed met the polishing requirements.