Surface Grinding Quality Of HIPSN Ceramics And Dressing Of Abrasive Tools

Engineering ceramic materials are favored in the high-end manufacturing field because of their excellent mechanical properties.Currently,grinding with super-hard grinding wheels is the main processing method for engineering ceramics.Grinding is the process of microscopic correlation between the grinding wheel and the workpiece in the grinding contact zone.In other words,the precision-formed tool causes local shear,fracture,and slip deformation of the workpiece material to achieve material removal,finally achieving the required size and processing quality of the part.In this paper,HIPSN(Hot-Isostatic Pressed Silicon Nitride)ceramics were studied by grinding test and grinding wheel dressing test.The removal mechanism of HIPSN ceramic material and the super-hard arc wheel dressing method were analyzed.And then HIPSN ceramics were optimized to achieve high-efficiency precision grinding.The specific research content is as follows:(1)The HIPSN ceramic grinding force measurement experiment was carried out.Through orthogonal experiments,the effects of process parameters such as grinding wheel speed,grinding depth and workpiece feed rate on normal and tangential grinding forces were studied under dry/wet grinding conditions.Based on ABAQUS,a finite element simulation model of single diamond abrasive grain cutting HIPSN ceramics was established to explore the influence of abrasive cutting speed and abrasive cutting depth on normal and tangential grinding forces.The impact on the stress distribution of diamond abrasive grains during HIPSN ceramic cutting is analyzed as well,and the test results verify the correctness of the simulation model.(2)Grinding process experiments were carried out under dry/wet grinding conditions to study the influence trends and influence degrees of grinding parameters on grinding quality,and the surface morphology of HIPSN ceramic are compared in dry/wet grinding conditions.Furthermore,the influence of cooling environment on the removal method and processing quality of HIPSN ceramic materials was analyzed.(3)The high-efficiency precised grinding process of HIPSN ceramics was optimized by analyzing the influence of grinding depth,workpiece feed speed and grinding wheel speed on surface roughness,surface waviness and surface topography under orthogonal test and single factor test to determine the optimal combination of process parameters.After optimization,the processing efficiency was greatly improved and the surface quality was improved.The removal mechanism of HIPSN ceramic materials was analyzed with the combination of experiments.(4)Aiming at the difficulty of dressing the arc-shaped super-hard grinding wheel and the low dressing precision,a vertical super-hard grinding wheel arc dresser was designed and manufactured to precisely trim the resin-bonded arc-shaped diamond grinding wheel.The surface roughness,arc precision,roundness and surface topography of round-shaped grinding wheels with different grain size were explored before and after dressing.Arc precision and roundness of the arc grinding wheel were greatly improved after trimming.In addition,the surface roughness of the grinding wheel was reduced,and the trimming exposed a large number of new abrasive grains.The vertical super-hard grinding wheel arc dresser and dressing method can precisely trim the arc grinding wheel,and the groove shape accuracy of the bearing ring grinding is greatly improved after dressing.The removal methods of HIPSN ceramic materials during grinding and the variation of surface grinding quality were analyzed through a large number of grinding tests and simulations.It provides a certain reference for high-efficiency and high-quality grinding of HIPSN ceramics and precision dressing of round-shaped grinding wheels.