Theoreticaland Experimental Studies Of Vibration-assisted Magnetic Abrasive Finishing Of Engineering Ceramics

There are more and more attentions on the precision technology of engineering ceramics parts,and varied finishing processing methods have been proposed.The vibration-assisted magnetic abrasive finishing(VAMAF) is based on the pure magnetic abrasive finishing(PMAF),which is accompanied with vibration in the processing. The advantage of the VAMAF is low finishing force,high accuracy,high efficiency and good surface integrity,due to its special machining trajectory and the effect of vibration-assisted.Because of the unique advantages of the VAMAF on the ceramics,the technology of the VAMAF has been studied, making the finishing of the engineering ceramics efficiently and precisely come true.The theoretical studies, surface quality and processing efficiency are carried out in the project. The process model of axial VAMAF of the inner surface of alumina ceramic tubes was built,and the processing character was analyzed.The effect of vibration on the motion character of the magnetic abrasive brush(MAB) was discussed,and the influence of amplitude.frequency,workpiece speed and feeding speed on the trajectory was clarified.Based on the indentation fracture mechanics,the model of material removal in ductile and brittle regime are established.In view of the requirements of high efficiency and precision machining of ceramic tube, the high efficiency and precision machining technology of the VAMAF was proposed, and the corresponding equipment was developed.A detailed study of the magnetic field in the VAMAF device was carried out by using finite element method, including the control of the finishing pressure and the design of the grinding head. With the help of ANSYS finite element software,the optimum design scheme was obtained by analyzing the finishing pressure under different working conditions.The character of material removal and surface roughness was investigated experimentally,making a comparison between the VAMAF and PMAF.The single factor test was applied to clarified the influence of amplitude,frequency,workpiece speed and feeding speed on the finishing character.The surface quality were researched from the micro topography, contour curve and surface residual stress,concluding that the VAMAF can get a better surface quality.