RE-Ba-Sb复合变质对4004铝合金组织与性能的影响

4004铝合金具有良好的可焊性。然而，由于其Si含量较高，在凝固过程中会形成粗大的Si相而降低该合金的塑性，从而降低箔材的成品率。为了提高该合金的塑性和成品率，采用RE?Ba?Sb对4004铝合金进行复合变质处理。作为对比，对该合金亦采用不同含量稀土进行变质处理。对于单一稀土变质处理，当稀土加入量为0.2%时，材料的组织和性能达到最佳，此时材料的的抗拉强度为194 MPa，伸长率为5%。对于RE?Ba?Sb复合变质处理，变质剂的最佳加入量采用正交设计的方法而进行优化。结果表明，RE的加入量影响最大，其次是Ba的加入量，Sb的加入量影响最小。三种元素的最佳加入量分别为RE 0.01%，Ba 0.3%，Sb 0.05%，此时材料的抗拉强度为224 MPa，伸长率为6%。且复合变质中RE的加入量约为单一RE变质加入量的1/20。

Effect of combined RE-Ba-Sb addition on microstructure and mechanical properties of 4004 aluminum alloy

As a brazing foil, 4004 Al alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. In order to improve the plasticity of 4004 Al alloy and subsequently improve the productivity of 4004 Al foil, 4004 Al alloy was modified by RE–Ba–Sb. As a comparison, the 4004 Al alloy was also modified by RE with different addition. The tensile properties of the alloy reach the best when the addition of RE was 0.2%, in which the tensile strength and elongation were 194 MPa and 5%, respectively. For RE–Ba–Sb modification, the addition of three elements was optimized by orthogonal analysis. The results showed that the greatest impact parameter of RE–Ba–Sb modification was RE addition, followed by addition of Ba and Sb. The optimum addition amounts of RE, Ba and Sb obtained by orthogonal analyses were 0.01%, 0.3%, and 0.05%, respectively. The tensile strength and the elongation of 4004 Al alloy modified by the optimal modification process were 224 MPa and 6%, respectively. The amount of RE addition in RE–Ba–Sb modification is lower than that in RE modification.