应力作用下2124合金蠕变时效的组织与性能

通过硬度测试、拉伸测试和透射电镜分析等方法,研究应力分别为0 MPa和200 MPa对Al-Cu-Mg系2124合金185℃时效后的硬度、强度以及伸长率的影响,阐述应力对2124合金时效后组织与力学性能的影响.研究结果表明:在常规时效和蠕变时效2种时效状态下,200 MPa应力作用下的蠕变时效使2124合金的S'析出相分布变得不均匀,合金的强度提高,而塑性降低；在0 MPa应力作用下,合金峰时效状态下的抗拉强度、屈服强度和伸长率分别为411.6 MPa,270.8 MPa,20.20％；在200 MPa应力作用下,合金峰值时效状态下的抗拉强度、屈服强度和伸长率分别为441.1 MPa,321.0 MPa和16.24％,后者的抗拉强度和屈服强度比前的高,但塑性低.

Microstructures and properties of 2124 alloy creep ageing under stress

The effects of stress on hardness,strength and plastic of 2124 Al-Cu-Mg aluminum alloy aged at 185 ℃ were investigated using hardness test,tensile test and transmission electron microscopy(TEM).In addition,TEM images of aged samples under 0 MPa and 200 MPa elaborated the influence of stress on the microstructure and mechanical properties of 2124 aluminum alloy.The results show that for both the aged conditions,creep age under stress of 200 MPa leads to the uneven distribution of S’ phase.S’ phase increases the strength of 2124 alloy,but the uneven distribution decreases the elongation.For the peak aged plates under 0 MPa and 200 MPa,the tensile strength,yield strength and elongation are 411.6 MPa,270.8 MPa,20.20% and 441.1 MPa,321.0 MPa,16.24%,respectively.Strength of the latter is higher than the former,while the elongation is lower.