Research on Wheel Wear and Grinding Performance of Elliptical Ultrasonic Vibration Assisted Grinding SiC Ceramics
In order to investigate the wear mechanism and grinding performance of wheel under elliptical ultrasonic vibration assisted grinding,SiC ceramics were selected as the processing object to conduct wheel wear tests on conventional grinding(CG)and elliptical ultrasonic vibration assisted grinding(EUVAG).Firstly,the VHX-5000 ultra-depth of field three-dimensional microscope is used to track and observe the micro morphology of wheel surface,and to characterize the form of grain wear,including statistics and analysis the grain wear platform area,grain cutting height,etc.,then reveal the influence of elliptical ultrasonic vibration on wheel wear mechanism;Secondly,analyzing the impact of the wheel wear on the grinding process(grinding force,specific energy,and material removal rate)and workpiece surface quality(surface roughness,micro morphology),as well as the variation of the main grinding performance of wheel with processing parameters under different wear states.Research has shown that compared to CG,EUVAG can reduce the proportion of large breakage and grain shedding,increase the wear platform area,and delay the descent speed in the grain cutting height.As the wear status increases,the grinding forces of the two grinding methods generally show a trend of rapid growth at first,followed by fluctuations,and then a slight decrease.The introduction of elliptical ultrasonic vibration can significantly reduce grinding specific energy(es),and the reduction amplitude ranges from 12.4％to 34.0％in the stable wear stage.Whether in CG or EUVAG,material removal rate(MRR)first increases and then decreases with the increase of wear state,and the MRR of EUVAG reaches the optimal value(38.2× 106 pm3/mm.s)at wear state 4;In the stable grinding stage,the scratch surfaces of both grinding methods are mainly characterized by brittle fracture,but the application of elliptical ultrasonic vibration helps to form a ductile smooth surface.In addition,higher wheel speed and lower workpiece feed speed are more conducive to reducing grinding force as a whole.Increasing the grinding speed is a direct means to reduce surface roughness in various wear states,but the workpiece feed speed for obtaining the lowest surface roughness varies under different wear states.
EUVAGSiCwheel weargrinding forcesurface quality of workpiece
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