The Ultra-smooth Surface Magnetorheological Processing Principles And Experimental Research

Aspheric optical part has made more and more influence on many fields such as national defence technology,aerospace and information. The development of surface accuracy of aspheric optical part is in great need of support of ultra-smooth surface polishing technology. Nowadays,an advanced polishing technology called magnetorhelogical finishing(MRF) technology,which can attain ultra-smooth surface without leaving cuticle layer,becomes a hot topic among researchers of many countries. Therefore,the research for MRF technology of aspheric optical part,will have great significance on the ultra-smooth surface polishing technology. In this dissertation,performance and mechanism of MRF is taken as the research subject and finally based on which parts of different kinds of materials polished preliminary to develop a MRF device for experiment has been developed preliminarily. Main research subjects are included as follow:At first,physical and chemical performance of magnetorheological (MR) fluid is studied,and it's magnetized character is introduced in details. This viscous liquid becomes a Bingham fluid,which is similar to half solid when a magnetic field is applied to it;stiffness is proportional to field strength directly. This phenomenon is very important to MRF performance.Secondly,by analysing of the theory of MRF,We set up a MRF device for experiment preliminarily. The device is devided into five parts,which includes adjustable magnetic field,circulating,clamping,storage for MR fluid and numeric control system. By introducing of specific design of every part in details,their realized function of every part is representated.Thirdly,the mechanism and features of MRF are introduced from microscopic view. The advantage of MRF is analyzing with the contrast of traditional polishing method. The result of MRF which is brought by the change of important factors are also discussed.At last,specific investigative experiments of MRF are carried on by the experimental device. In the experiment,we change important parameters of MRF,and get many useful data. From this result,mechanism and theory of MRF are analysed and certified. The idea of computer numeric control MRF with the algorithm of resident time is also put forward.