Preparation Of Diamond Grinding Wheel For Forming Grinding Using Inter-Sand Electroplating And Brazing Process

Forming grinding technology is increasingly used in the processing of hard and brittle materials and high-plasticity metal materials.However,grinding wheels used for forming grinding on the market have the problems of low abrasive edge height,poor wear resistance,and easy falling off.Grinding wheels prepared by brazing process have the advantages of high abrasive edge,good wear resistance and so on.Therefore,applying the brazing process to the preparation of diamond grinding wheels will become a new trend.However,in the brazing process,there are problems such as the fine-grained diamonds are not evenly distributed on the substrate,and diamonds are thermally damaged at high temperatures which restricts the development of brazing fine-grained diamond tools.In order to solve the problem of brazing technology in this text,a compound process method which combines the electroplating of sand buried method with the brazing is put forward.This composite process solves the problem of uneven distribution of fine grained particles by electroplating,and the brazing technology solves the problem of the combination of the abrasive and the matrix.However,the electroplating of sand buried method and brazing process also brings some problems,such as the uneven thickness of the brazing layer,the hard melting of the brazing material,and the difficulty of the brazing.Therefore,the solutions are further proposed in this paper:(1)Pre-dressing of the brazing layer to ensure the thickness of the solder layer.(2)A quantitative Cu powder is added to the brazing alloy to solve the problem that the excessive Ni element introduced in electroplating cause the hard brazing of the solder.(3)Use the high frequency induction brazing,the rotating heating of the matrix method,the grinding wheel is heated evenly,the flow of the filler metal is small,and the heat damage of the diamond is small.Finally,the optimum process route for the preparation of diamond grinding wheel by electroplating and brazing is explored through experiments.The results show that:(1)Form grinding wheels was prepared through composite technology,microstructure of diamond and filler with good interface and enriched with Cr,Cr element reacts with C element in the diamond to generate Cr3C2 and Cr7C3 two kinds of carbides;Protrudent height of diamond is close to half the size of diamond chip,The abrasive have a larger large space to hold wear debris.(2)After adding Cu into the alloy,bond reacts with the diamond,use Raman spectrum to scanning analysis the diamond,result showed that the diamond did not appear graphitized.Cu reacts with alloy to generate solid solution,which made the hardness of the alloy increase.(3)the evaluation of the grinding performance of the formed diamond wheel confirms that the self-made brazing grinding wheel has better grinding performance than the electroplated grinding wheel,and the brazing tool has the advantages of better molding accuracy,longer service life and better wear resistance.