CAJ | 학술논문

通过常规拉伸性能测试、扫描电镜(SEM)和透射电镜(TEM)观察，研究少量Mg、Ag、Zn多元微合金化对一种新型Al-Cu-Li合金微观组织与拉伸性能的影响。结果表明：在T6、T8时效态下，该合金的抗拉强度(σb )和屈服强度(σ0.2)均大于不含Mg、Ag、Zn的另外3种合金的，而伸长率(δ)相差较小。其主要强化析出相为大量的T 1相、部分θ′相和少量的S′相。在T6时效态下，Mg、Ag的同时存在大大促进T 1相和S′相的析出，显著增加合金强度；Mg、Zn的同时添加也促进T 1相和S′相的析出，使合金强度在一定程度上得到提高。Mg元素微合金化的强化效果最强，同时添加Ag和Zn或单独添加Ag或Zn均能增强其强化效果；无Mg存在条件下，添加Ag、Zn对合金的强化效果较小。在T8时效态下，时效前的预变形形成的大量位错成为T 1相的形核点，使合金形成细小、密集和均匀弥散分布的T1相，削弱了Mg、Ag、Zn元素对合金时效析出过程的影响。
통과상규랍신성능측시、소묘전경(SEM)화투사전경(TEM)관찰，연구소량Mg、Ag、Zn다원미합금화대일충신형Al-Cu-Li합금미관조직여랍신성능적영향。결과표명：재T6、T8시효태하，해합금적항랍강도(σb )화굴복강도(σ0.2)균대우불함Mg、Ag、Zn적령외3충합금적，이신장솔(δ)상차교소。기주요강화석출상위대량적T 1상、부분θ′상화소량적S′상。재T6시효태하，Mg、Ag적동시존재대대촉진T 1상화S′상적석출，현저증가합금강도；Mg、Zn적동시첨가야촉진T 1상화S′상적석출，사합금강도재일정정도상득도제고。Mg원소미합금화적강화효과최강，동시첨가Ag화Zn혹단독첨가Ag혹Zn균능증강기강화효과；무Mg존재조건하，첨가Ag、Zn대합금적강화효과교소。재T8시효태하，시효전적예변형형성적대량위착성위T 1상적형핵점，사합금형성세소、밀집화균균미산분포적T1상，삭약료Mg、Ag、Zn원소대합금시효석출과정적영향。
The effects of Mg, Ag and Zn multi-alloying on tensile properties and microstructure of a new Al-Cu-Li alloy were investigated by means of tensile test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the tensile strength (σb) and yield strength (σ0.2) of the new Al-Cu-Li alloy are higher than those of the three alloys without Mg, Ag and Zn, respectively, while the elongation (δ) is almost the same in T6 and T8 temper. The main strengthening phases are plenty of T 1 phase, part ofθ′phases and a little of S′phase. In T6 temper, the additions of Mg and Ag accelerate the precipitation of T 1 and S′phase which improves the strength prominently. Mg and Zn also accelerate the precipitation of T 1 and S′phases, which improve the strength to some extent. The microalloying of Mg shows the strongest strengthening effect, while adding both of Ag and Zn or adding Ag or Zn separately can enhance the strengthening effect of Mg. Without the presence of Mg, the additions of Ag and Zn have little effect on the strengthening. In T8 temper, the predeformation before aging forms plenty of dislocations which become the precipitation sites of T 1 phase, making finer, dense and uniform T 1 phase in the matrix, which weakens the effects of Mg, Ag and Zn on the aging behavior of the new Al-Cu-Li alloy.