微量Sc对高强铸造Al-Zn-Mg-Cu合金组织和力学性能的影响  

Influence of trace Sc on the microstructure and mechanical properties of high strength Al-Zn-Mg-Cu alloy

作　　者：许永祥 龚家林 张宝尧 李向平 马俊成 XU Yongxiang;GONG Jialin;ZHANG Baoyao;LI Xiangping;MA Juncheng(CRRC Qishuyan Institute Co.,Ltd.,Changzhou,Jiangsu 213011,China)

机构地区：[1]中车戚墅堰机车车辆工艺研究所股份有限公司,江苏常州213011

出　　处：《轨道交通材料》2024年第5期20-24,共5页Materials for Rail Transportation System

摘　　要：为了开发铸造用高强铝合金,通过金相显微镜、扫描电镜的观察以及拉伸试验机、布氏硬度计的检测,研究了微量Sc对Al-Zn-Mg-Cu合金显微组织和力学性能的影响。结果表明,Sc的添加能够显著细化晶粒并提高合金力学性能,铸态合金的抗拉强度由179.3 MPa提高至203 MPa;经热处理后,硬度提升明显,非平衡共晶相消失,且有Al7Cu2Fe相残留;含Sc合金的抗拉强度、屈服强度和伸长率分别为591.7 MPa、516.7 MPa和4.2%,分别提高了22%、14.1%和320%。In order to develop high-strength aluminum alloy for casting application,the effect of trace Sc on the microstructure and mechanical properties of Al-Zn-Mg-Cu alloy is studied with the aid of metallographic microscope,scanning electron microscope,tensile testing machine and Brinell hardness tester.The results indicate that the addition of Sc can significantly refine the grain size and improve the mechanical properties of the alloy.The tensile strength of the as-cast alloy increases from 179.3 MPa to 203 MPa;After heat treatment,the hardness dramatically increases,the unequilibrium eutectic phase disappears,leaving residual Al7Cu2Fe phase.The tensile strength,yield strength,and elongation of the Sc containing alloy reach 591.7 MPa,516.7 MPa,and 4.2%,respectively,representing an increase of 22%,14.1%,and 320%,correspondingly.

关 键 词：微量SC 高强铝合金 细化晶粒 显微组织 力学性能 

分 类 号：U270.41[机械工程—车辆工程]