Study On The Reciprocating Magnetorheological Polishing Experimental Machine&Preparation And Property Of Polishing Fluid

With the rapid development of science and technology,modern products on the surface quality of parts is increasingly higher and higher.Many products on the surface quality requirements have been reached nanometer level.The surface quality of the workpiece which is reached nanometer level is generally called a ultra smooth surface.The most typical application of ultra smooth surfaces is the optical components in the instrument and equipment in aviation,aerospace,medical and national defense industry.There are some defects with the traditional polishing method used to manufacturer the ultra smooth surface,for example low efficiency,surface layer damage,or uneasy to control.In the early 90s of last century,the magnetorheological polishing technology was invented with the magnetorheological fluid applying to polishing.It overcome the shortcomings of the traditional polishing.Therefore,the MRF technology of optical element has a more and more irreplaceable role in ultra precision machining area.However,the research on the magnetorheological polishing in China started late,and the gap between the foreign countries is large.So it is significant to study the magnetorheological polishing technology.In the field of magnetorheological polishing,the main concern of the domestic and foreign scholars is the surface roughness and surface machining accuracy,but there is not too much attention on the surface texture uniformity etc.The texture of the surface of the optical element directly affects its performance,good optical surface should be uniform texture and isotropic anisotropic of its surface texture.As the traditional wheeled magnetorheological polishing machine is magnetic field generator fixed and single lines polishing,it will produce anisotropic texture for the surface of the workpiece.Therefore,the research group of Northeastern University proposed a new type of reciprocating magnetorheological polishing machine.In this thesis,we mainly research on this type of reciprocating magnetorheological polishing machine,and make a preliminary test and research work,including the following aspects:(1)Refer to many domestic and foreign reference,magnetorheological fluid,magnetorheological polishing and magnetorheological polishing machine development and present situation are described.For the process of polishing existing polishing lines single and polished surface texture anisotropy,we proposed reciprocating magnetorheological polishing machine.(2)We designed a reciprocating magneorheological polishing experiment machine,including the overall structure,magnetic field generating device,reciprocating device and fixture,and used ANSYS finite element software to analyzed magnetic field generator of magnetic field distribution.According to simulation results of magnetic field generator,the reciprocating stroke were analyzed and on the magnetic field generating device is used for practical test.(3)Magnetorheological fluid components and their characteristics,and magnetorheological fluid properties are analyzed.The magnetorheological polishing fluid preparation process and proportion is researched.Then we prepare magnetorheological polishing fluid for magnetorheological polishing.Last we test the performance parameters of preparation of magnetorheological polishing fluid,including rheological property,viscosity and stability.(4)The mechanism of the traditional glass polishing and the mechanism of the removal of the reciprocating magnetic rheological polishing is analyzed.Based on the Preston equation,the mathematical model of the material removal for the magnetorheological polishing is established by solving the shear stress and normal pressure.(5)A reciprocating magnetorheological polishing experiment is carried out.The feasibility of the test bed and the magnetorheological fluid of the reciprocating magnetorheological polishing is verified.The change of the surface roughness before and after the test,and the removal efficiency of the reciprocating magnetorheological polishing are analyzed.Through the research of this paper,it is indicated that the design of the reciprocating magnetic rheological polishing test rig and the preparation of the magnetorheological finishing solution is feasible,and can be used for polishing glass and other materials.The results of this study have a certain reference value and engineering significance to the development of this kind of reciprocating magnetorheological polishing machine tool in the future.