Optimization of cryogenic milling parameters for AFRP

This paper is aimed to restrain the defects such as fluff and ablation, which were often found in machining of the aramid fiber-reinforced composites (AFRP). The cooling method of spray liquid nitrogen was adopted in the orthogonal milling process. The processing parameters including cutting depth, cutting speed, cooling temperature, feed speed, and liquid nitrogen flow were considered in details, and their effects on the processing quality were researched and analyzed. The analysis optimization methods of processing parameter were employed for the influence on the machining surface quality. Meanwhile, the optimal machining surface quality was predicted and verified. The results show that the cryogenic way realizes a bigger improved role on machining quality than the conventional one for AFRP. As well as the influence order of processing parameters on the roughness is cutting depth, cutting speed, cooling temperature, feed speed, and liquid nitrogen flow. And the predicted result Ra = 0.557 mu m of minimum surface roughness value is similar with the actual one Ra = 0.572 mu m and verifies the feasibility of optimization method. For processing of AFRP, the cooling way of spray liquid nitrogen has a positive role with high quality and efficiency.