Si元素及预时效对6016型铝合金塑性的影响

Effect of Si and pre-ageing on the tensile ductility of 6016 aluminum alloy

制备了不同硅含量的6016型铝合金,并通过拉伸试验对未预时效及预时效合金的力学性能、加工硬化能力、应变速率敏感性系数(SRS)进行了测试和分析。结果表明,增加硅含量,可提高试验合金的初始加工硬化率,降低动态回复程度,进而可提高合金的加工硬化能力。同时增加硅含量,也能提高合金的应变速率敏感性系数。因而,增加合金中的硅含量能够改善其塑性。而经过预时效后,由于降低了合金的加工硬化以及应变速率敏感性系数,对合金的塑性有不利的影响。

6016 aluminum alloys with different Si contents were prepared,the pre-aged and/or naturally aged alloy sheets were tensile tested,and mechanical properties,work hardening and strain rate sensitivity（ SRS） were analyzed. The results show that increasing Si content can enhance the initial work hardening rate and decrease the dynamic recovery rate,thus a high work hardening capability can be observed in high Si content alloy. Moreover,increase of Si content can also increase the SRS. Therefore,with enhanced work hardening capability and SRS,tensile ductility can be improved in high Si content alloy. Once pre-aged,the work hardening capability and SRS are decreased,resulting in a poor tensile ductility.