Introduction Hot forming of aluminum alloys is challenging due to complex thermo-mechanical coupling and the difficulty of accurately controlling defects such as thinning, springback, wrinkling, and tearing. To improve forming quality and process stability, this study optimizes the hot-forming process for Al 6063-T5 alloy. Methods Hot tensile tests were conducted using an electronic universal testing machine to obtain dynamic stress–strain curves at different temperatures and strain rates. Based on these data, a strain-coupled improved Arrhenius high-temperature constitutive model was established. A U-shaped mold cooling system and hot-stamping platform were designed to monitor temperature variations in real time and evaluate the dynamic interfacial heat transfer coefficient (IHTC). A VUMAT subroutine incorporating the constitutive model and dynamic IHTC was developed, and a finite element model was established. The material processing parameters and forming process curve were optimized using an orthogonal experimental design, supported by both simulations and experiments. Results The ductility of Al 6063-T5 increased with increasing temperature within the investigated range, while the flow stress was significantly affected by both temperature and strain rate. A pre-pressure holding–secondary forming process strategy was proposed. The optimal parameter combination was identified as a stamping speed of 125 mm/s, an initial temperature of 350 °C, a single-side blank-holder pressure of 10 MPa, and a holding time of 0.8 s. Experimental validation showed that the optimized sheet thickness increased by an average of 48.770% on the left side and 45.262% on the right side. Springback was reduced by an average of 44.708% at the upper rounded corner and 35.786% at the lower rounded corner. Discussion The optimized process effectively improved thickness uniformity and reduced springback while preventing obvious forming defects such as tearing and wrinkling. The proposed constitutive modeling approach, dynamic IHTC implementation, and pre-pressure holding–secondary forming strategy provide theoretical support and practical engineering guidance for hot forming of aluminum alloy components.
Wang et al. (Tue,) studied this question.