Dry Mill-grinding Of AlSiC Composite Materials By Monolayer Brazed Diamond Wheel

Due to the higher strength and modulus, high temperature resistance, wear resistance, high thermal conductivity, and the advantages of adjustable coefficient of heat, in the aerospace, AlSiC composite material was widely used in aerospace automotive, electronics, military industry. The higher hardness of SiC and higher plasticity of aluminium matrix, make this material hard to machine with traditional and non-traditional methods. Single layer brazed diamond grinding wheel owns higher protrusion and chip space, and shows with a superior sharpness. In this study, single layer brazed diamond gringing wheel was used to machine AlSiC composite material with different SiC contents. The grinding force, temperature, surface integrity of AlSiC composite, character of chips and the wear of grind wheel have been investigated. The main research content includes the following aspects:(1) The grinding force of single layer brazed diamond grinding wheel on AlSiC composite was studied. By grinding AlSiC composite material with different SiC contents using single layer brazed diamond grinding wheel with different mesh size, the relationship between grinding force on mesh size of diamond grits, SiC contents were investigated, it was found that grinding force decreases with the increases of abrasive mesh, the grinding force for AlSiC composite material with different SiC contents can be ranked with the sequence of:50%、70%and20%. We also analysed the sharpness of grinding wheel with different mesh size of diamond grits when grinding AlSiC composite material with different SiC contents.(2) The grinding temperature of single layer brazed diamond gringing wheel machine AlSiC composite was studied. By using single layer brazed diamond grinding wheel with different mesh size of diamond grits on AlSiC composite material with different SiC contents, the relationship between grinding temperature with mesh size of diamond grits and SiC contents was investigated. It was found that grinding temperature decreases with the increases of mesh size of diamond grits, the grinding temperature for AlSiC composite material with different SiC contents can be ranked with the sequence of:50%、70%and20%.(3) Surface integrity of AlSiC composite and the character of chips under different processing conditions were also studied. The material removal mechanism was analysed by observing surface morphology and chip form. It wa found that the mode of material removal of AlSiC composite material can be classified by removal of aluminum alloy matrix only and the removal of matrix and SiC simultaneously.(4) The grinding ratio and the wear of the brazed diamond grinding wheel were also studied. It was found that the grinding ratio is decreased with the increase of mesh size of diamond grits for AlSiC composite with low content of SiC. However, for the AlSiC with higher content of SiC, the grinding ratio is increased with the increase of mesh size. In this study, the wear of diamond grits is not severe, and the main form is abrasive wear and microchipping.