Simulation and experimental study on milling mechanism and tool wear of low volume SiCp/Al composites

Silicon carbide particles reinforced aluminum matrix composites are widely used in national defense and related high-end technology fields due to their excellent mechanical properties. To explore the milling mechanism and tool wear mechanism of low-volume SiCp/Al composites in high velocity milling, the milling experiments for 20% volume SiCp/Al2009 composites were performed using a polycrystalline diamond (PCD) tools. A three-dimensional milling model of SiCp/Al composite was established considering the random distribution of SiC particles, the influence of milling parameters on surface quality was comprehensively analyzed and its cutting mechanism was described, and the wear forms and mechanism of PCD tools were revealed during milling of SiCp/Al composites. The result showed that the cutting depth is the main factor affecting the machined surface quality, followed by the spindle speed, and the feed rate has the smallest effect on it. It was observed that when spindle speed (n) was 17,000 r/min, the feed rate (f) was 8 mm/min, the depth of cut (a(p)) was 0.04 mm, the surface roughness value was the smallest, Ra was 0.056 mu m. The surface morphology was mainly manifested as pits, cracks, burrs, and so on, subsurface defects included particle breakage, peeling, and matrix cracks, and the tool wear forms included chipping, flaking, and bond wear.