摘要
研究了０４９Ａｌ－Ｌｉ合金的时效组织和室温拉伸性能以及改变Ｃｕ，Ｍｇ含量对合金组织和性能的影响，实验结果表明，在人工时效状态，０４９合金中的析出强化相为Ｔ１相．由于Ａｇ和Ｍｇ的添加促进了Ｔ１相的析出而使合金获得高的强度。减少０４９合金中Ｃｕ的含量或增加Ｍｇ的含量都导致Ｔ＿１，相析出数量的减少，从而降低合金强度，对少量Ａｇ，Ｍｇ促进Ｔ＿１相析出的机制进行了讨论。
The microstructure and mechanical properties of the 049 Al-Li alloy were studied，and the effect of change in Cu，Mg contents on the microstructure and properties was also invest-gated．TEM observations showed that the strengthening phase present in the 049 alloy agedat 160 ℃ was T_1 phase；Ag and Mg additions promoted the precipitation of T_1 phase. Thehigher strength of the 049 alloy resulted from the large volume fractions of T_1 precipitates.The decrease in Cu content and increase in Mg content in the 049 variants resulted in the de-crease in T_1 precipitates，so the strength of the alloys was decreased． The roles of Ag and Mgin stimulating the precipitation of T_1 phase were discussed.
基金
国家"八五"科技攻关计划基金
