Study On Two Dimensional Ultrasonic Vibration Assisted Polishing Process And Its Equipment

With the development of aviation,aerospace,mobile communication,national defense,automobile manufacturing and other fields,the requirements of dimensional accuracy,surface shape accuracy and shape accuracy are higher and higher,especially the surface roughness.So far,industry and academia have done a lot of research,and put forward some very valuable non-traditional polishing processes,such as ultrasonic polishing,ultrasonic vibration assisted polishing,ion beam polishing,magnetic field assisted polishing,flow field assisted polishing,airbag polishing,laser polishing.Ultrasonic vibration assisted polishing,which has been widely studied at home and abroad,has been used in aerospace,precision optical instruments and other fields.Based on Lissajous curve,the motion trace of two dimensional ultrasonic vibration assisted polishing is studied,the closeness of Lissajous curve is studied,and the optimal uniformity algorithm is studied.Based on the classical empirical formula Preston equation,the removal function of two-dimensional ultrasonic vibration assisted polishing is studied.On this basis,the coordinate transformation between the polishing tool and the workpiece and the cutting effect of abrasive particles in the polishing fluid are studied,and the material removal efficiency of three common motion cases is compared.The algorithm of 3D surface reconstruction based on two-dimensional color image is studied.The edge detection of gray image and the line detection based on Hough transform are used to determine the color area.The color bar mapping function is established by piecewise linear fitting.Based on the relevant knowledge of the deformation of elastic medium in solid mechanics,the theoretical magnification and shape factor of the exponential ultrasonic horn are derived.This paper studies the rotation ability of various kinds of common flexure hinge,and finally studies the theoretical rotation error of flexure hinge.The three-dimensional models of six kinds of common flexure hinges are established.Under the action of constant load,the deformation ability of all kinds of flexure hinges lays the foundation for the selection of flexure hinges in the follow-up work.Based on Newton's second theorem,the differential equation of the system is established.According to the differential equation of the system,the mass matrix,stiffness matrix and damping matrix of the system are sorted out respectively.Then the simulation analysis is carried out by MATLAB Simulink and Newmark-?.The improvement of material removal rate of polishing process by abrasive particles in ultrasonic atomization was studied.Using a four-axis ultra precision grinding machine,a comparative experiment was carried out to study the role of ultrasonic atomization compared with the ordinary polishing process.The results show that the ultrasonic atomization assisted polishing can significantly improve the removal efficiency of materials,which is about 1.5 times of the ordinary polishing.In addition,it can provide polishing for the workpiece used in the two-dimensional ultrasonic vibration assisted polishing,and improve the efficiency of the workpiece in the ordinary polishing process Surface quality before experiment.The influence factors of two dimensional ultrasonic vibration assisted polishing were studied by orthogonal experiment.The final research shows that the relationship between speed,pressure and maximum depth is positive correlation.The greater the rotational speed,the greater the maximum removal depth of the material.The greater the pressure is,the greater the maximum removal depth is.Moreover,the smaller the diameter of the polishing tool,the greater the material removal depth.The relationship between speed,pressure and maximum depth is positive correlation.The higher the rotating speed,the greater the material removal rate.The greater the pressure is,the greater the material removal rate is.Moreover,the larger the diameter of the polishing tool,the larger the material removal rate.The effect of rotational speed on material removal efficiency and depth is more obvious.