论文部分内容阅读
研究Mg、Zn添加对一种Al-Cu-Li合金微观组织演变及力学性能的影响。结果表明,Mg、Zn的添加促进了δ′相的形核析出,并且可以降低其长大速度,因而使得合金中的δ′相更加细小弥散。在时效早期,含Mg和Zn的合金中析出大量的GP区,而不含Mg只含Zn的合金中没有看到GP区的存在,只有少量粗大的θ′相;含Mg不含Zn的合金中也有较多的GP区生成,这说明Mg促进GP区的形成,Zn单独作用对GP区形成无太大影响,只有和Mg一起作用时起到加速GP区形成的作用。随着时效的进行,含Mg和Zn的合金中GP区转变成θ′/θ′′相,而不含Mg只含Zn的合金中θ′相无明显变化,含Mg不含Zn的合金中也有大量θ′/θ′′相生成。说明Mg是促进θ′/θ′′相形成的主要元素,而Zn只是在有Mg的存在下起到促进其形成的作用。
The effects of Mg and Zn addition on the microstructure evolution and mechanical properties of Al-Cu-Li alloys were investigated. The results show that the addition of Mg and Zn promotes the nucleation of δ ’phase and reduces the growth rate of δ’ phase, which makes the δ ’phase of the alloy more finely dispersed. In the early stage of aging, a large number of GP zones were precipitated in Mg and Zn containing alloys, but GP zones were not found in Mg-free alloys with only a few coarse θ ’phases; Mg-free alloys containing Zn There are also more GP regions generated, which indicates that Mg promotes the formation of GP region. Zn alone has no significant effect on the formation of GP region, and only plays an important role in accelerating the formation of GP region when acting together with Mg. With aging, the GP zone in the alloy containing Mg and Zn was transformed into the θ ’/ θ’ phase, whereas the alloy without Zn and Mg had no significant change in the θ ’phase. In the alloys containing Mg and Zn, There are also a large number of θ ’/ θ’ phases generated. It is shown that Mg is the main element that promotes the formation of θ ’/ θ’ ’phase, while Zn plays a role of promoting its formation only in the presence of Mg.