摘要
采用水冷铜模.激冷铸造法,制备了三种Sc和Zr含量不同的Al-Zn-Mg-Cu合金薄板材,测试了合金经120℃时效不同时间后的拉伸性能,利用光学显微镜和透射电子显微镜观察了合金的显微组织。结果表明:采用Sc和Zr复合微合金化可明显细化合金的铸态晶粒组织,抑制合金的再结晶,大大提高合金的强度;Sc含量越高,晶粒细化效果越好,合金强度提高也越大;微量Sc和Zr在Al-Zn-Mg-Cu合金中主要以Al3(Sc,Zr)质点的形式存在,初生Al3(Sc,Zr)粒子是在合金凝固过程中形成的,主要起非均质形核的作用,次生Al3(Sc,Zr)粒子是合金在均匀化处理和后续热处理中析出的,起亚结构强化和直接析出强化作用。
Three kinds of Al-Zn-Mg-Cu alloys containing Sc and Zr were prepared by ingot-metallurgy processing. Tensile mechanical properties of the studied alloys aged at 120℃ for various times were investigated. The microstructure of the studied alloys at different treatments was observed by optical microscope and transmission electronic microscope. The results show that （i）minor Sc and Zr addition can produce substantial grain refinement and remarkably improvement of the strength, strength of the Al-Zn-Mg-Cu alloys improve with the increasing of Sc addition; （ii）Minor Sc and Zr in Al-Zn-Mg-Cu alloys mainly exist as Al3 （Sc, Zr）, primary Al3 （Sc, Zr） can refine the casting structure, secondary Al3 （Sc, Zr） can produce precipitation strengthening and substructure strengthening.
出处
《轻合金加工技术》
CAS
北大核心
2005年第9期41-43,54,共4页
Light Alloy Fabrication Technology
