Fine Turning of SiCp/Al Composite Pistons

摘要

The paper deals with the surface quality of machined silicon carbide particulate aluminium matrix composite pistons. The influence of machining parameters, cutting speed, feed rate, and depth of cut on surface finish was investigated during cutting tests using polycrystalline diamond (PCD) tools. The surface roughness was measured and the influence of the cutting parameters was analyzed. The machined surface morphology was examined by scanning electron microscopy (SEM). The results show that the machined surface quality is determined by the cutting parameters and the material's microstructure. The surface roughness of the SiC_p/Al composite pistons satisfy the demanding of parts when the cutting speed is higher than 250m/min, the feed rat is lower than 0.2mm/rev and depth of cut is lower than 0.2mm. But in general, the surface quality of the composite is inferior to its matrix alloy. The measurements of the cross-section microhardness indicate the sub-surface affecting zone confined to the top 50-60μm.