Milling of disc cutter replacing traditional grinding mechanism in machining of nickel-based superalloy honeycomb composites under ice-freezing condition

The nickel-based superalloy honeycomb composite (NBSHC) is widely applied in aerospace and defense due to its low density, high-temperature resistance, and excellent specific strength. Although grinding is the conventional method for machining NBSHC, its efficiency and quality are limited. Therefore, disc-cutter milling is proposed as an alternative, offering higher efficiency and reduced defects. The micro and macro simulations of NBSHC milling and grinding were established to reveal the intricate mechanisms involved in material removal process. Combining the experiments and simulations, the cutting force, temperature, plastic deformation and defect behavior were comprehensively analyzed to explain the mechanism of milling of disc cutter replacing grinding. The findings revealed that during NBSHC milling with a disc cutter, the cutting forces were minimized, resulting in lower temperatures and thus reducing the region of deformation and thermal softening effects. The material removal occurred through cutting, with a shear surface forming the contact zone, where stress, energy and plastic strain were concentrated. This concentration facilitated easier material removal and chip formation. Hence, the influence area of plastic deformation was extremely small, only concentrated at the top of the honeycomb wall and the tiny burr. These reasons minimized the occurrence of severe defects during NBSHC milling with a disc cutter. While ensuring that the machining quality meets practical requirements, replacing grinding with disc cutter milling for NBSHC increased the efficiency by a factor of 33.