Executive Summary : | In response to the ever-growing need to reduce weight, using aluminum alloys for manufacturing auto-body components has gained momentum in recent years. However, poor formability and high springback often limit the intricate shaping of aluminum alloy sheets. The proposed electric-hot forming and in-die quenching (E-HFQ) aims to significantly enhance the formability of high-strength aluminum alloy sheets in an energy-efficient manner. The technique can save up to 50% time with improved precision compared to established high-temperature formability improvement methods. The proposed work has a high potential for commercialization and can be a lucrative step toward sustainable manufacturing and circular economy. In this work, a customized E-HFQ setup will be developed, where the blank placed inside the die is directly heated using electric current followed by forming and in-die quenching process. This process enables quick blank heating and improves formability due to thermal softening. The effect of electro-plasticity can also support improved formability. The high-strength heat-treatable AA7xxx sheet, which is highly considered in automotive body manufacturing, will be selected for this study. The current-temperature relation will be optimized to develop a suitable temperature feedback-dependent control panel. The mechanical characterization at different temperatures will be done through tensile tests by heating the sample through direct electric current. Accurate measurement of material flow behavior and anisotropy will be performed using digital image correlation (DIC). Finite element (FE) simulation of E-HFQ processes will be carried out using LSDYNA software. The validated results can be used for in-depth analysis via coupled and decoupled effects of electric and thermal effects on formability. An E-HFQ formability window considering optimized current-temperature relations will be established by evaluating the forming limit diagram and limiting drawing ratios. An A-pillar reinforcement panel, which is an essential component in automotive cars, will be manufactured to demonstrate the applicability of the process. Springback and post-formed part profiles will be measured to depict the achievable geometrical accuracy. Finally, the strength and surface quality of the component will be studied through pre- and post-forming hardness and roughness testing. |