Effect of graphite particles on machinability of SiC/Gr/Al composites

SiC/Gr/Al composites with the graphite particle size of 1, 6 and 20 μm were fabricated by squeeze casting technology and the effects of graphite particles on machinability were investigated. Results show that with increasing size of graphite particles, the tool wear has very little change, but the cutting force decrease noticeably. Compared to SiC/Al composite, the cutting forces increase steadily with increasing the cutting speed during machining SiC/Gr/Al composite, the tool life is prolonged 42 and 59%, respectively, at speed of 20 and 30 m min− 1 when machining SiC/Gr(6 μm)/Al composite. It is a result of the solid lubrication of graphite particle preventing for growth of adhesive wear.