稀土铒对Al-Cu-Mg-Ag-Zr合金微观组织与时效行为的影响  

Effect of trace addition of Er on microstructure and ageing behavior of Al-Cu-Mg-Ag-Zr alloy

作　　者：李云涛[1] 刘志义[1] 夏卿坤[1] 余日成[1] 刘延斌[1] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《材料热处理学报》2007年第2期49-53,共5页Transactions of Materials and Heat Treatment

摘　　要：研究了稀土元素铒对Al-Cu-Mg-Ag-Zr合金微观组织以及165℃时效特性的影响。力学性能测试结果表明:合金中添加稀土Er对合金的强度贡献不大,但可大幅度提高合金的塑性变形能力。显微组织分析表明:添加稀土Er主要以Al8Cu4Er相和少量固溶于基体的形式存在于合金中,Al8Cu4Er相在合金变形过程中细化,对合金起到异质强化的作用。合金中Er原子和空位发生强交互作用,阻碍Ag、Mg原子团的形成,抑制了Ω相形核,延迟Al-Cu-Mg-Ag-Zr合金在165℃人工时效响应。The effect of trace addition of Er on the ageing characteristics and mierostrueture of Al-Cu-Mg-Ag-Zr alloy was investigated. The results show that Al8 Cu4 Er phase and a small quantity of solid solution of Er is the main form of Er in the as-cast alloy. Small addition of Er has little influence on strength, but increases the ductility of the alloys significantly. The increased plasticity deformation ability depends on dehydrogenation of Er in alloy. TEM observation shows that the morphology of Ω precipitation can be modified by the small addition of Er. The trace Er affects the microstructure by reducing the density of Ω precipitates. It can be concluded that the strongly interaction between Er and vacancy inhibits the forming of Ag-Mg cluster which is believed to promote precipitation of Ω phase.

关 键 词：铝合金 稀土Er Al8Cu4Er 时效特性 微观组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]