铒含量对6061铝合金铸轧板材组织性能的影响

Effect of Erbium Content on Microstructure and Properties of Cast-Rolled 6061 Aluminum Alloy Sheet

文章研究了微量Er元素对双辊铸轧6061铝合金板材微观组织演变的影响。采用NF6-300立式双辊铸轧机制备不同Er含量的6061铸轧板材,采用金相组织观察、扫描电镜和透射电镜等组织分析技术,分析了合金中Er的主要存在形式和作用机制。结果表明,添加微量的Er可以在铸轧板中形成初生Al_(3)Er相,该相组织中可以成为α-Al优良的异质形核核心,可大幅细化6061铝合金铸轧板材晶粒。而且,Er与Fe之间产生交互作用,组织中针条状和骨骼状的富Fe相转变为较小的短棒状和块状。但铸轧板中的Er含量过多时,Er元素聚集,含Er稀土化合物和杂质相尺寸明显增大。

In this paper,the effect of trace Er elements on the microstructure evolution of double-roll cast 6061 aluminum alloy sheet is studied.The NF6-300 vertical double-roll casting and rolling mechanism is used to prepare 6061 casts and rolled plates with different Er content,and the main forms and mechanism of Er in the alloys are analyzed by metallography observation,scanning electron microscopy and transmission electron microscopy.The results show that the addition of trace Er can form a primary Al_(3)Er phase in the cast-rolled plate,which can become an excellent heterogeneous nucleus core ofα-Al in the phase organization.The grains of 6061 aluminum alloy cast-rolled plate can be greatly refined.In addition,Er and Fe interact with each other,and the Fe-rich phase of needle and skeletal-like in the tissue is transformed into smaller rod and block.However,when the content of Er in cast-rolled plate is too much,Er elements accumulate,and the size of rare earth compounds and impurity phases containing Er increases obviously.