Machining of Sic - Metal Matrix Composite (MMC) by Polycrystalline Diamond (PCD) Tools and Effect on Quality of Surface by Changing Machining Parameters

In this paper, wear of polycrystalline diamond (PCD) cutting tools and the surface integrity during machining of SiC – Metal Matrix Composite (MMC) is discussed. An attempt is made to establish relation between the hardness of the tool and the flank wear. A newly developed PCD tool, which is superior in hardness with lower flank wear than the conventional tools is introduced. During machining with PCD tools, the severity of transfer material on the tools increased significantly with cutting distance and cutting speed. The superior surface finish obtained with the PCD tools cannot be merely explained by their low wear. The low degree of adhesion that these tools had with the work material appeared to be the main reason for the superior surface obtained at both low and high cutting speeds. At low cutting speed, when the use of coolant resulted in a marked reduction in the amount of work material on the machined work pieces, high Ra and P-V values can be obtained.