| CoCrMo alloy,which has good corrosion resistance,outstanding biocompatibility,suitable physical and chemical properties,has been widely used as a medical implant material.In this paper,ELID grinding technology is applied to CoCrMo alloy grinding,and we study its grinding mechanism,variation of grinding force and surface quality,friction and wear properties,corrosion resistance,so that we can understand the grinding processability of CoCrMo alloys deeply.We studied in the following aspects:First,we analyze the forming mechanism and function of oxide film on ELID grinding wheel,clear the composition of oxide film on grinding wheel surface,theoretically,and then propose the model of composite abrasive grains consist of oxide film and abrasive grains.Second,we research the micro structure of oxide film,element,shape,grains size,and covering parcels situation of oxide film which surround abrasive grains,and the forming mechanism of composite abrasive grains.Then,we analyze the ELID grinding force of CoCrMo alloy theoretically,the correctness of the theory is verified by the grinding force test.Whether it is normal force or tangential force,the grinding force increases with the grinding depth and speed,decreases with the grinding wheel,the result is in line with theoretical research.Next,the surface roughness of the CoCrMo alloy with different grinding wheel size,workpiece speed and grinding depth was measured and analyzed under ELID grinding,and we observed the micro-topography of the CoCrMo alloy by three-dimensional microscope and measured the wear and friction coefficient of the CoCrMo alloy under different parameters.Finally,we studied the corrosion resistance of CoCrMo alloy under ELID grinding,the passivation layer formed on the surface of CoCrMo alloy after ELID grinding.The results of XRD and SEM show that the CoCrMo alloy surface contains oxygen,which forms various oxides.Therefore,it has better corrosion resistance and biocompatibility. |
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