Study On The Effect Of Wear Of Diamond Abrasive Grain On The Removal Process Of Single Crystal Silicon Carbide

Single crystal silicon carbide has a wide range of applications in electronics,aerospace and military industries due to its excellent physical and mechanical properties.Grinding is the main processing method for single crystal silicon carbide precision machining,and the study of single abrasive grain processing is a prerequisite for in-depth exploration of the grinding process.During the grinding process,due to the interaction between the diamond abrasive grain and the workpiece,diamond abrasive grain is worn or even broken,then the workpiece material is removed,and the shape of the diamond abrasive grain changes greatly.In the past research,the shape of the diamond abrasive grain is one of the important factors affecting the material removal process.Therefore,this article takes diamond abrasive grain and single crystal silicon carbide(SiC)as the research objects.Through the method of single abrasive grain scratch test,the <111> and <110> crystal planes of a single diamond abrasive grain are used to scratch the carbon(C)surface and silicon(Si)surface of the single crystal SiC.The damage process and typical damage morphology of the diamond abrasive grains <111> and <110> crystal planes were analyzed.The different crystal planes of the diamond abrasive grain were damaged,the morphology was characterized and detected,and the effect of the damage of diamond abrasive grains on the removal mechanism of single crystal SiC material was further analyzed.Finally,the relationship among the critical damage amount,the morphological key parameters and scratching force was deduced by simulation based on smooth particle hydrodynamics(SPH).The main work of this article is summarized as follows:(1)Through a single abrasive scratch test,the breakage laws of diamond abrasive grains were compared and analyzed,and the characteristic parameters of diamond abrasive grains were characterized.The damage process of diamond abrasive grains <111> and <110> crystal planes and the typical shape corresponding to the damage process was analysed.(2)Observed the morphology of the scratches on the surface of the workpiece after the diamond abrasive grains of different damage forms scratch the single crystal silicon carbide with three-dimensional video microscope,and compared the cracks,chippings,and scratch widths on the scratched surface;The depth of the scratch and the volume of the removed material were measured by laser scanning confocal microscope.(3)Three-dimensional dynamic simulations based on the SPH method of the process of diamond abrasives grain scratching single crystal SiC were conducted.The simulation results agree well with the experimental results.Simulation results show that the damage area of diamond is basically consistent with the damage of diamond.(4)The relationship among the critical damage parameters of diamond abrasive grains(breaking angle and length of cutting edge),the morphological key parameters and scratching force were investigated based on the simulation of SPH method.The model of effect between diamond abrasive grains and single crystal silicon carbide material was established.The simulation results show that the scratching force during the scratching process increases with the increase of the abrasive particle angle.The change of the abrasive grain angle has no significant effect on the subsurface damage depth,and the width of the scratch has a negative correlation with the abrasive grain angle.Scratch force,subsurface damage depth and scratch width of the workpiece are negatively related to the cutting edge length during the scratching process;the change of the cutting edge length of the diamond abrasive grains has a greater impact on the material removal process than the angle of the abrasive grains.