Mg、Si含量对Al-Cu-Mg-Ag-Si合金析出相的影响

Influence of Mg and Si Content on Precipitates of Al-Cu-Mg-Ag-Si Alloy

研究了Mg、Si元素含量对Al-Cu-Mg-Ag-Si合金实际析出相种类及性能的影响。结果表明,Al-Cu-Mg-Ag-Si合金中高Mg含Si合金析出了大量S相和粗大的第二相;低Mg低Si合金中析出了常见的θ相和Ω相;低Mg含Si合金中出现了6系铝合金中常见的σ相和β″相等多种析出相,且具有非常细小弥散的θ相,为合金提供了良好的强化效果。Si和Mg的存在均极大地改变了合金的析出序列,无法通过增加Mg含量抵消Si的作用。Si的加入显著抑制了Ω相的析出,而大幅增加Mg含量则会促进S相的析出。

The influence of Mg and Si content on the types and properties of actual precipitates in Al-Cu-Mg-Ag-Si alloy was investigated.The results show that a large amount of S phase and coarse second phases exist in the Al-Cu-Mg-Ag-Si alloy with high Mg content and regular Si content;the commonθphase andΩphase are precipitated in the low-Mg and low-Si alloy;the common second phases in 6xxx aluminum alloys,such asσandβ″phases,appear in the alloy with low Mg content and regular Si content,and also fine and dispersedθphases are precipitated in the alloy,which results in excellent strengthening effect of the alloy.Both Si and Mg greatly alter the precipitation sequence of the alloy,and the effect of Si cannot be offset by increasing Mg content.The addition of Si significantly inhibits the precipitation ofΩphase,while a considerable increase of Mg content can promote the precipitation of S phase.