An Investigation of the High-Speed Machinability of 7050 Aluminum Alloy Based on Different Prefabricated Crystal Orientations

Abstract

This study investigated the high-speed cutting performance of 7050 aluminum alloy with prefabricated crystal orientations under dry-cutting conditions. Three specimens with different crystal orientations were prefabricated using pre-deformations of 10, 15, and 20%, and the effects of cutting parameters on cutting force, surface morphology, and tool wear were analyzed. The results showed that the three-dimensional cutting force initially increased and then decreased with the increase in cutting speed. In addition, the three-dimensional cutting force increased with the increase in cutting depth and feed rate. Under the same cutting parameters, the three-dimensional cutting force of 7050 aluminum alloy was in the following order: 20% pre-deformation > 10% pre-deformation > 15% pre-deformation. During high-speed cutting, different degrees of plowing, bulging, and sticky chips appeared on the machined surface, and the surface morphology of the 15% pre-deformed 7050 aluminum alloy was better than that of the other two pre-deformed 7050 aluminum alloys. During the high-speed cutting process, tool wear mainly occurred in the forms of collapse edge, adhesion, flaking, and breakage, and wear mechanisms were usually adhesive, diffusion, and oxidation wears. Under the same cutting parameters, the tool wear of the 15% pre-deformed 7050 aluminum alloy was lighter.