加钪对Al-Zn-Mg-Cu-Zr合金组织性能的影响  

Effect of Sc Addition on Microstructures and Mechanical Properties of AI-Zn-Mg-Cu-Zr Alloys

作　　者：胡国强[1] 夏长清[1] 戴晓元[1] 刘昌斌[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《有色金属加工》2005年第3期7-10,共4页Nonferrous Metals Processing

基　　金：基金项目:国家重点基础研究发展规划项目(国家973计划项目)(G1999064911-2)

摘　　要：本文研究了微量钪对 A1-Zn-Mg-Cu-Zr 合金组织及性能的影响。钪在铝合金中主要以两种形式的化合物存在,一种是合金凝固时从熔体中析出的一次 Aj_3(Sc,Zr)相,另一种是铸锭均匀化时析出的二次 Al_3(Sc,Zr)相。前者是α(Al)晶粒细化剂,可有效细化铸态晶粒;后者可强烈牵制晶粒内位错及亚晶界,有效阻止热轧、退火或固溶处理过程中的再结晶。钪是产生强烈析出强化的合金元素,同不加钪的铝合金相比,含0.30%Sc的 Al-Zn-Mg-Cu-Zr 合金的抗拉强度和延性显著提高。The effect of minor Sc addition on the microstructures and mechanical properties of Al-Zn-Mg-Cu-Zr alloys is studied.In these alloys,minor Sc mainly exist in two forms of scandium aluminides containing Zr,one is primary Al_3(Sc,Zr)precipitated from the melt during solidification,the other is secondary Al_3(Sc,Zr)precipitated during homogenization.The former is the most effective grain refiner for α(Al)matrix and results in as-cast grain size refinement,the latter is coherent with the matrix and can strongly pin subboundaries, which can effectively restrain recrystaliization of the alloys during hot rolled,annealing and solid solution.Scandium is one of the alloying elements that produce a very intensive precipitation hardening effect.Compared with the alloy without Sc addition,the Al-Zn-Mg-Cu-Zr alloy with 0.30% Sc addition exhibits remarkable higher tensile strength and ductility.

关 键 词：含钪铝合金 显微组织 机械性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]