晶内固溶度的影响
(1. 大连理工大学 材料科学与工程学院,大连 116024;
2. 北京航空材料研究院,北京 100095)
摘 要: 分别采用电磁铸造和普通连铸技术制备Al-Zn-Mg-Cu-Zr合金,研究电磁场对合金显微组织、合金元素晶内固溶度的影响。结果表明:采用电磁铸造技术制备的Al-Zn-Mg-Cu-Zr合金具有良好的表面质量和内部组织;电磁场显著提高合金元素在晶内的固溶度,减小了微观偏析程度。相对于普通连铸,电磁铸造法制备的Al-Zn-Mg-Cu-Zr合金的晶粒平均尺寸从68 mm减小到53 mm,Zn、Mg和Cu元素的晶内相对溶质固溶度分别由56%、62%和25%提高到79%、74%和44%。
关键字: Al-Zn-Mg-Cu-Zr合金;电磁铸造;普通连续铸造;显微组织;相对溶质固溶度
solid solubility inside crystals of Al-Zn-Mg-Cu-Zr alloy
(1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
2. Beijing Institute of Aeronautical Materials, Beijing 100095, China)
Abstract:Al-Zn-Mg-Cu-Zr aluminum alloys were prepared by electromagnetic casting (EMC) and direct chill casting (DCC), respectively. The effects of electromagnetic field on as-cast microstructure and alloy elements solid solubility inside crystals of Al-Zn-Mg-Cu-Zr aluminum alloy were investigated. The results show that the Al-Zn-Mg-Cu-Zr alloy billets prepared by EMC have better surface qualities, microstructures and higher solid solubility inside crystals of alloy elements. The degree of microsegregation in the EMC billet decreases. Compared with the DCC specimens, the average grain size of the EMC specimens decreases from 68 μm to 53 μm, moreover, the relative intracrytalline solubilities of elements Zn, Mg and Cu increase from 56%, 62% and 25% to 79%, 74% and 44%, respectively.
Key words: Al-Zn-Mg-Cu-Zr alloy; electromagnetic casting; direct chill casting; microstructure; relative intracrytalline solubility