Effects of Ce and Impurities on Percentage Elongation and Recrystallization in Al-Li Alloys

The effects of the contents of Ce and deleterious impurities on the ductility and recrystallized microstructure have been investigated for Al Li based alloys 2090 and 8090 sheets. The relationships between the parameters of recrystallized microstructure and percentage elongation( δ ) in the transverse orientation of the sheets have been obtained. The beneficial behavior of Ce microalloying can be markedly shown in the alloy 2090 containing a certain amount of impurities Fe and Si or in the alloy 8090 containing a certain amount of impurities Na and K. Ce microalloying can still improve δ to a certain degree, even though impurities Fe, Si, Na and K coexist and their concentration is rather high in the alloy 8090. When the recrystallized volume, coarse grained volume and grain average width increase because of the variation in the contents of Ce element and impurities, δ decreases for the alloys 2090 and 8090. When the grain aspect ratio increases, δ increases for the alloy 2090 and decreases for the alloy 8090.

铝锂合金中铈与杂质含量对延伸率及再结晶的作用

研究了铈及有害杂质含量对２０９０及８０９０铝锂合金薄板延伸率和再结晶状态的影响，得出了再结晶组织参数与板材横向延伸率之间的关系。Ｃｅ的微合金化作用在含一定量Ｆｅ、Ｓｉ杂质的２０９０合金和含一定量Ｎａ、Ｋ杂质的８０９０合金中表现得比较明显，当各种杂质共存且含量较高时，Ｃｅ对８０９０合金的延伸率仍有一定的有利作用。随Ｃｅ及杂质含量变化，若两类合金的再结晶体积、粗晶体积及晶粒平均宽度增加，则其延伸率下降，随晶粒长宽比增加，２０９０合金的延伸率增加而８０９０合金的延伸率下降。