A Study On The Preparation Of Brazed Diamond Grinding Wheel By Fiber Laser Micro-machining And The Grinding Performance

AlSiC composite materials own higher specific strength, specific modulus, high-temperature resistance, wear resistance and adjustable thermal conductivity which and t lead it widely used in the aeropace, automotive, electronics and military fields. So it’s precision and ultra-precision machining is paid more attention. Brazed diamond wheel own higher bonding strength, larger chip space and better sharpness. At present, the diamond grains of brazed diamond grinding wheel are usually limited in the range of coarse mesh size (larger than 200 mesh) due to the difficulty of manufacturing technology and the diamond graphitization. In present study laser micro-machining technology is used to prepare the brazed diamond grinding wheel with micro-cutting edges, and the grinding performance of the wheel grinding on AlSiC is to be investigated.The micro-machining rules on diamond grit and CVD diamond film by the fiber laser is studied. The relationship between the of the micro-machined groove and the parameters of laser machining (pulse width, scanning speed and scanning times) is also analyzed. It was found that is increased with the increasing of deeper and pulse width and the scanning times. The faster of scanning speed can cause the narrower and shallower of the microgroove. In the micro-machining, the width and depth of the micro-groove on single crystal diamond is higher than that of CVD diamond film due to the difference of thermal conductivity. Finally, by selecting proper laser parameters and three different machining paths, three type of V grooves can be obtained on CVD diamond film.The diamond brazed grinding wheel with micro cutting edges is prepared and it’s grinding performance on AlSiC is also investigated. The surface morphology of ground AlSiC, the wear of the wheel and the chips characteristics are observed. The results showed that the The diamond brazed grinding wheel with micro cutting edges can grind AlSiC smoothly, and the grinding force is significantly reduced than brazed diamond grinding wheel. SiC particles in AiSiC in the grinding is pulled up or fractured, to form the micro-defects of the surface. Micro-fracture along the micro-grooves is found to be the main wear form of diamond grits as well as the large fracture and polishing, the main brittleness removal processed materials, grinding debris were very fine powders. The grinding wheel with micro-cutting edges owns higher rate of micro-fracture of diamond grits than normal brazed diamond wheel, which improve the sharpness of the grinding wheel, force, which is more suitable for grinding AlSiC.