【摘要】 针对当前铝合金超低温成形技术研究中构件形状简单和较少关注尺寸精度的问题，建立复杂车身构件超低温成形工艺研究平台，并进行了铝合金AA6111-T4构件的超低温成形研究，在成形性、尺寸精度和力学性能三个方面将超低温成形构件与室温成形构件进行对比。研究结果表明超低温成形技术可在不改变构件力学性能的前提下实现更高的壁厚均匀性，证明了其成形复杂形状零部件的优势和能力，这是材料超低温变形条件下应变硬化指数升高导致的。然而，也同时发现铝合金超低温成形构件存在回弹量大的现象，这可能和超低温下材料强度较高有关，未来需进一步发展相应的回弹预测和调控方法。研究结果有望促进铝合金超低温成形技术在车身复杂薄壁构件制造中的研究和应用。更多还原

【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.更多还原