含Sc超高强度铝合金成分优化及组织性能研究  

Study on the composition optimization and microstructure properties of super high-strength aluminum alloy with scandium

作　　者：宫子琪 郑理银 GONG Ziqi;ZHENG Liyin(School of Mechanical Engineering,Tianjin Sino-German University of Applied Sciences,Tianjin 300350,China;School of Materials Science and Engineering,Tianjin University of Technology,Tianjin 300384,China)

机构地区：[1]天津中德应用技术大学机械工程学院,天津300350 [2]天津理工大学材料科学与工程学院,天津300384

出　　处：《有色金属科学与工程》2025年第1期75-84,共10页Nonferrous Metals Science and Engineering

基　　金：天津市教委科研计划资助项目(2019KJ139)。

摘　　要：本文以铸态Al-8.67Zn-2.5Mg-2.5Cu铝合金为研究对象,利用Jmatpro软件模拟计算合金相图与性能,确定较优的Sc元素添加量及其热处理工艺,并通过电弧炉制备合金铸锭,研究合金元素Sc及固溶时效工艺对试样的组织演变影响,探讨合金强化机理。结果表明:当添加0.25%的Sc元素时合金的抗拉强度和硬度单次提升量最大,并且可以避免Al3Sc的偏聚现象。Al-8.67Zn-2.5Mg-2.5Cu-0.25Sc合金的数值模拟硬度和抗拉强度分别为139.13 HV和424.12 MPa。合金较优的均匀化、固溶和时效热处理工艺制度为475℃/24 h+482℃+25℃/16 h。当冷却介质的冷速大于174.23℃/s,试样固溶的转移时间小于0.42 s时可以抑制第二相析出,进而获得过饱和固溶体。铸态铝合金均匀化热处理后的硬度、抗拉强度和延伸率分别为139.86 HV、432.1 MPa和10.31%,固溶时效后其硬度、抗拉强度和延伸率分别提高了35.42 HV、146.6 MPa和2.4%。With Al-8.67Zn-2.5Mg-2.5Cu aluminum alloy as the research object,using Jmatpro software to simulate and calculate the alloy phase diagram and properties,the optimal amount of Sc element added and its heat treatment process was determined,and alloy ingots were prepared through electric arc furnace.The influence of Sc element and solid solution aging process on the microstructure evolution of the sample was studied,and the strengthening mechanism of the alloy was explored.The results indicate that the tensile strength and hardness of the alloy were maximized when 0.25%Sc element was added,and the polarization of Al 3 Sc can be avoided.The numerically simulated hardness and tensile strength of the Al-8.67Zn-2.5Mg-2.5Cu-0.25Sc alloy are 139.13 HV and 424.12 MPa,respectively.The optimal heat treatment process for the alloy,including homogenization,solid solution,and aging,is 475℃/24 h+482℃+25℃/16 h.By cooling the samples at a cooling rate greater than 174.23℃/s and transferring them to the solid solution for less than 0.42 seconds,second-phase precipitation can be inhibited,resulting in an oversaturated solid solution.After homogenization heat treatment of the as-cast aluminum alloy,the hardness,tensile strength,and elongation are 139.86 HV,432.1 MPa and 10.31%,

关 键 词：含钪铝合金 热处理 JMatPro软件 金相组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]