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Due to the demand of environmental protection and fuel economy, reducing weight of vehicles was a major goal of the automobile industry. The use of lightweight material such as aluminum, magnesium to replace the traditional steel was an efficiency way to reach this target. However, low formability and unpredictable spring-back condition of aluminum alloy resultant the difficulty in practical applications. In addition, relatively less die developing experience for aluminum alloys caused high developing cost and time. In order to avoid the above situation, this study cooperated with Cobra King Industry Co., Ltd. to study the formability of aluminum alloy fender panel. In this study, the CAE software PAM-STAMP was used to analyze the formability of the aluminum alloy fender panel. Then, based on the simulation results, optimize the formability. The forming parameters were adjusted to improve the defects such as sheet cracking and wrinkle, and to achieve a perfect die face. The analysis of internal strain, plastic flow deformation and forming limit are also used to understand the forming conditions. The die face was modified according to the simulation results, and the sheet material was modified to fully extend and reduce the spring-back condition. Results show that the optimize formability can be achieved in the condition of the pressing force is 450kN, die removal line radius is 12mm, bead radius is 7mm. Regarding to the reliability, the results were compared with the CAE software by using field trials to confirm the correctness of the CAE. After the defects of the formed sheet are improved, the PAM-STAMP optimization function was used to modify the die surface to reduce the spring-back. The original upward spring-back amount was 4.02mm, which was reduced to 0.3mm upward and the effect on the sheet before and after compensation was used to understand the rebound condition, and the material was modified to meet the tolerance standard. This analysis method is more effective than the conventional method in shortening the time course of the die face design and reducing the waste of material and cost caused by trial and error.
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