新型Er、Zr微合金化Al-Zn-Mg-Cu合金在均匀化中的显微组织演变（英文）

发布时间：2018-04-20 07:34

本文选题：Al + Zn　；参考：《Transactions of Nonferrous Metals Society of China》2017年07期

【摘要】：通过使用光学显微镜、扫描电镜、透射电镜及X射线衍射等手段研究一种新型Er、Zr微合金化Al-Zn-Mg-Cu合金在均匀化过程中的显微组织演变。结果表明:铸态合金组织存在严重的偏析,此时合金中含有大量的T(AlZnMgCu)、S(Al_2CuMg)和Al_8Cu_4Er相,这些初生相大量偏聚于晶界。随着在465°C单级均匀化处理的进行,第二相含量大幅度降低,可熔的T相和S相会逐步地熔入基体,但Al8Cu4Er相不能完全消除,仍有少量残留。相对于单级均匀化工艺,合金在双级均匀化处理时不仅能够消除铸态合金偏析组织,而且能够析出大量细小弥散分布的L1_2结构的Al_3(Er,Zr)相。结合均匀化动力学分析,可以得出合金合理的均匀化热处理制度为(400°C,10 h)+(465°C,24 h)。
[Abstract]:By means of optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffraction, the microstructure evolution of a new type of Erning-Zr microalloyed Al-Zn-Mg-Cu alloy during homogenization was studied. The results show that there is a serious segregation in the microstructure of the as-cast alloy, and the alloy contains a large number of Tzn-ZnMgCuCU and Al_8Cu_4Er phases, and these primary phases tend to converge on the grain boundaries. With the homogenization treatment at 465 掳C, the content of the second phase decreased significantly, and the fusible T and S phases would melt into the matrix gradually, but the Al8Cu4Er phase could not be completely eliminated, and there was still a small amount of residual phase. Compared with the single-stage homogenization process, the alloy can not only eliminate the segregation structure of the as-cast alloy, but also precipitate a large number of Al _ S _ 3O _ (er _ (Zr)) phases with a small dispersion of L _ (12) structure during the two-stage homogenization treatment. Combined with the homogenization kinetic analysis, the reasonable homogenization heat treatment system of the alloy is 400 掳C ~ (10 h) ~ 465 掳C ~ (-1) 24 h ~ (-1).
【作者单位】：北京工业大学材料科学与工程学院;
【分类号】：TG146.21;TG292

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