Study on Milling Mechanism and Surface Roughness of CNTS/2009Al Composites

Carbon nanotube aluminum matrix (CNTs/Al) composites have broad development prospects in the aerospace field. The removal mechanism and surface morphology of CNTs/Al composites during milling were studied, and the optimal parameters of CNTs/Al milling were explored. It is of great theoretical and practical value to promote the further application of CNTs/Al. In this paper, ABAQUS software was used to simulate the milling process of CNTs/Al composites, and the milling mechanism was revealed. Orthogonal experiments and single-factor experiments were designed. The machined surface morphology was observed and analyzed by laser confocal microscopy, and the milling parameters and the surface quality of the material were explored. The side surface damage was studied by scanning electron microscopy. The results show that the influence of milling parameters on surface roughness was as follows: feed rate, milling depth, and spindle speed. After milling, the main removal forms of carbon nanotubes were fracture, pull-out, and indentation into the matrix. The main defects on the surface were burrs, pits, cavities, and microcracks. With the increase in feed rate, the surface quality of CNTs/Al composites would decrease, and there would be more pits. When the spindle speed was 10,000 r/min, the feed speed was 6 mm/min, and the milling depth was 0.02 mm, the minimum surface roughness was 0.048 μm. Mastering the milling mechanism of milling CNTs/Al composites and the influence of milling parameters on surface quality plays a guiding role in actual milling and is of great significance for improving processing efficiency.