Machinability of pure copper before and after processing by severe plastic deformation method

For using ultrafine-grained metals and alloys in industry, further machining sequences and studying their possible effects are necessary to attain these products in their ultimate dimensions. In this work, the machinability of ultrafine-grained pure copper and the corresponding coarse-grained counterpart investigated systematically. The results showed that the processed copper could be machined as efficiently as its initial one. Also, the machining of the Cu sample with the polycrystalline diamond tools requires much less force than tungsten carbide tools. The produced cutting forces were smaller for the processed copper as compared to the initial copper. Also, similar tool wear mechanisms were detectable for the copper specimen before and after the process. Chip morphology altered less through the machining, and the surface quality enhanced during machining the ultrafine-grained copper. Eventually, the polycrystalline diamond tool increased the surface roughness of initial and processed specimens since it caused less than 50% roughness compared to the tungsten carbide tool.