合金成分与热处理对6xxx系铝合金力学性能的影响

研究合金成分（Mg，Si，Cu）和热处理（自然时效和预时效）对6xxx系铝合金力学性能的影响。结果表明：合金成分与热处理不仅影响材料的成形性能，而且影响材料的烘烤硬化性能；提高合金中Si含量或Si／Mg比或添加0．3％Cu，可显著提高材料的韧性和成形性能，而预时效将减低材料的韧性和成形性能。对所研究合金的强度、韧性、加工硬化、应变敏感性、成形极限和烘烤硬化性进行了比较和总结。

Effect of alloy composition and heat treatment on mechanical performance of 6xxx aluminum alloys

The effect of alloy composition and heat treatment, including natural ageing and pre-ageing, on the mechanical performance of eight 6xxx alloys designed with systematically varying Si, Mg and Cu contents was studied. The results show that not only the alloy composition and heat treatment before forming influence the formability, but also they have an effect on the paint bake response of the alloys. Increasing the alloy Si content, decreasing Mg/Si ratio and adding 0.3% Cu （mass fraction） were generally found to improve the tensile ductility and formability of the alloys studied, while pre-ageing was found to decrease these properties. A full property profile of these alloys in terms of strength, tensile ductility, work hardening, strain rate sensitivity, forming limit and paint bake response was presented.