Experimental study on the evolution of chip morphology, chip formation, and surface topography with cutting parameters, and their relationships in dry milling of cast aluminum alloy with PCD inserter

The evolution of chip morphology, chip formation, and surface topography (Ra, Rz) with cutting parameters has become an increasingly important way to achieve higher manufacturing efficiency and better surface topography. In this investigation, the relationships of chip morphology, chip formation, and surface topography with respect to cutting parameters are developed in dry milling of cast aluminum alloys with a PCD inserter. The feed rate affects the surface roughness, although no unanimous trend is observed between cutting parameters and surface topography. Surface crack propagation directly affects the saw-tooth chip morphology and the surface topography. The chip morphology is transformed from saw-tooth to continuous type at a chip deformation ratio of 3; chip deformation ratios of 2.5, 1.875, and 1.25 achieve cutting velocities of 32.71, 35.98, and 39.25 m/s, respectively, in which a continuous chip is formed by surface crack propagation and the predominant effect of thermal softening and surface topography is significantly improved.