外加载荷对2124合金微观组织和性能的影响

Effect of Additional Load on the Performance and Microstructure of 2124 Alloy

采用透射电镜、拉伸等实验研究了2124合金在190和170℃加载时效后的组织和性能的变化规律.结果表明,由于位错提供了足够的错配度,S相在各个方向上的取向和数量基本相同;外加载荷对Al-Cu-Mg合金中S相的择优取向没有较明显的影响,但其尺寸相对较小,外加载荷对GPB的尺寸和取向分布都没有影响;在190℃加载时效时S相的长大速率比在170℃要快;在相同时效条件下,大量析出较细的S相使施加载荷样品的屈服强度要高于未施加载荷的样品.

Microstructure and performance were investigated on aged 2124 alloy at 190 and 170 ℃ with or without added load by means of TEM,tensile testing.Due to dislocations providing enough misfits for the nucleation of S phases,equivalent S phase distribution in various directions was obtained.Load did not significantly impact preferential orientation of the S phase.However,length of the S phase in aged samples with load was shorter than that without load.Load had no significant impact on preferential orientation and length of GPB.Growth rate of the S phase aged at 190 ℃ was faster than that at 170 ℃ with load.Because of a large amount of fine S phase precipitation,yield strength of the aged alloy with load was larger than that without load.