非平衡凝固Al-4.73Mg-0.71Sc-0.33Zr合金的组织及时效析出行为  

Microstructure and aging precipitation behavior of non-equilibrium solidified Al-4.73Mg-0.71Sc-0.33Zr alloy

作　　者：王杰 杨伟 应国民 徐勇 WANG Jie;YANG Wei;YING Guo-min;XU Yong(National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室,江西南昌330063

出　　处：《材料热处理学报》2024年第5期55-61,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52061032,52261014);江西省教育厅资助项目(DA202203113)。

摘　　要：采用真空感应熔炼、铜模喷铸和时效处理相结合的方法,研究了不同冷速条件下Al-4.73Mg-0.71Sc-0.33Zr合金的凝固组织演化规律及其析出相的析出行为。结果表明:铸态合金组织由粗大的α-Al基体和Al3(Sc,Zr)微米颗粒组成;经铜模喷铸后,非平衡凝固(快冷)合金的平均晶粒尺寸由铸态的250μm显著下降至7.5μm,同时Al3(Sc,Zr)颗粒相的生长受到抑制;快冷合金经300℃时效45 min后,析出大量纳米Al3(Sc,Zr)相,合金显微硬度由79.86 HV0.2提高至121.95 HV0.2,相比原始快冷合金提高52.70%。The solidification microstructure evolution and precipitation behavior of Al-4.73Mg-0.71Sc-0.33Zr alloy under different cooling rates were studied using a combination of vacuum induction melting,copper mold spraying and aging treatment.The results show that the microstructure of the as cast alloy is composed of coarse α-Al matrix and Al3(Sc,Zr)micron-scale particles.After being sprayed into a copper mold,the average grain size of the non-equilibrium solidified(rapidly cooled)alloy decreases from 250μm for as cast alloy to 7.5μm,and the growth of Al3(Sc,Zr)particle phase is inhibited.After aging at 300℃ for 45 min,a large amount of nano-scale Al3(Sc,Zr)phase is precipitated in the rapidly cooled alloy,and the micro hardness of the alloy increases from 79.86 HV0.2 to 121.95 HV0.2 which is 52.70% higher than the original rapidly cooled alloy.

关 键 词：Al-4.73Mg-0.71Sc-0.33Zr合金 非平衡凝固 时效析出 显微硬度 

分 类 号：TG146.2[一般工业技术—材料科学与工程]