Study on Improving the Formability of 2B06 Aluminum Alloy Sheet by Local Hardening Effect Using Laser Heat Treatment

Aiming at the difficulty of forming complex parts of 2B06 aluminum alloy, the idea of using local hardening by laser heat treatment to improve the formability of sheet metal was put forward. Based on the experimental study of hardening effect on aluminum alloy sheet by laser heat treatment, the peak temperature field of laser spot path and its surrounding heat-affected area was calculated by numerical simulation, and its accuracy was verified by actual temperature measurement. A sheet billet model coupled with mechanical property gradient was proposed and constructed to study the deep drawing formability of cup parts with laser local hardening using both simulation and experimental methods. The results show that the laser scanning method can form a stable gradient temperature field and has little influence on the surrounding non-heated area, and big property gradient sheet blanks with different widths can be designed by multi-pass scanning. Mechanical properties tests show that laser heat treatment can effectively improve the local hardening ability of aluminum alloy. This effect can effectively prevent the thinning of large deformation area at round corners during cup drawing, thus improving the drawing formability of sheet metal. Based on the above mentioned, the laser local heat treatment is applied to the forming of 2B06 aluminum alloy aviation complex frame parts. By designing the laser treatment path and parameters, the reasonable local hardening area can be obtained, which can effectively avoid the crack caused by excessive thinning at the reinforcement area, and greatly improve the formability of complex parts. © 2022 Editorial Office of Chinese Journal of Mechanical Engineering. All rights reserved.