Abstract: Research was conducted to address the issues of simple component shapes and the lack of attention to dimensional accuracy in current studies on cryogenic forming technology for aluminum alloys. A cryogenic forming platform for complex automotive body components was established, and cryogenic forming research was conducted on AA6111-T4 aluminum alloy components. The cryogenic formed components were compared with room temperature formed components in terms of formability, dimensional accuracy, and mechanical properties. The results show that cryogenic forming can achieve higher wall thickness uniformity without changing the mechanical properties of the components, demonstrating its ability to form complex-shaped parts. This is due to the higher strain hardening exponent of the material during ultra-low temperature deformation. However, it has also been observed that aluminum alloy components formed at cryogenic temperatures exhibit significant springback, which may be attributed to the higher material strength at such low temperatures. In the future, it is necessary to further develop methods for predicting and controlling springback. The results of this study are expected to promote the research and application of cryogenic forming technology for aluminum alloys in the manufacturing of complex thin-walled components for vehicle bodies.

Key words: 6-series aluminum alloy, cryogenic forming, formability, dimensional accuracy, mechanical properties