电磁场频率对半连续铸造Al-Zn-Mg-Cu合金组织与性能的影响  

Effects of Electromagnetic Field Frequency on Microstructure and Mechanical Properties of Al-Zn-Mg-Cu Alloy Prepared by Direct Chill Casting

作　　者：王睿 张浩宇 王顺成 吴锡坤 WANG Rui;ZHANG Hao-yu;WANG Shun-cheng;WU Xi-kun(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,Liaoning,China;Guangdong Institute of Materials and Processing,Guangzhou 510651,Guangdong,China;Guangdong Xingfa Aluminum Co.,Ltd.,Foshan 528137,Guangdong,China)

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870 [2]广东省材料与加工研究所,广东广州510651 [3]广东兴发铝业有限公司,广东佛山528137

出　　处：《铸造》2020年第3期240-245,共6页Foundry

基　　金：广东省科学院院属骨干科研机构创新能力建设项目(2018GDASCX-0117);广东省科技厅公益研究与能力建设项目(2017A070701029)。

摘　　要：采用低频电磁场半连续铸造技术制备直径200 mm的Al-Zn-Mg-Cu合金圆棒,利用光学显微镜、扫描电子显微镜(含EDS)和拉伸试验机,研究了电磁场频率对Al-Zn-Mg-Cu合金圆棒显微组织与力学性能的影响。结果表明:随着电磁场频率的逐渐增加,圆棒横截面的α-Al晶粒逐渐从枝晶转变为等轴晶,晶粒尺寸减小,Zn合金元素的偏析程度减小,晶间MgZn_2相和Al_3Fe相的尺寸逐渐细化,合金圆棒的拉伸力学性能提高。当电磁场频率增加到45Hz时,圆棒心部的抗拉强度和断后伸长率分别为308.27 MPa和8.55%,圆棒边部的抗拉强度和伸长率分别为322.40 MPa和11.96%,与未施加电磁场的圆棒相比,此时圆棒心部与边部组织性能差异减小。Al-Zn-Mg-Cu alloy bar with a diameter of 200 mm has been successfully prepared through the low-frequency electromagnetic field(LFEF).The microstructure and mechanical properties of the as-synthesized samples are characterized by optical microscope,scanning electron microscope and electronic tensile testing machine.The experimental results demonstrate that the increase of the LFEF frequency results inα-Al grains change from dendrites to equiaxed grains,decreases the size of grains and the degree of segregation of Zn element,refines the sizes of the intergranular MgZn2 phase and the Al3Fe phase,and improves the tensile mechanical properties of the round bar.The tensile strength and elongation after fracture of the alloy show a significant increase at the center(308.27 MPa and 8.55%)and the edge(322.40 MPa and 11.96%).Compared with the round bar without applying an electromagnetic field,the difference between the center and the edge of the rod in the microstructure and mechanical properties shortens.

关 键 词：AL-ZN-MG-CU合金 半连续铸造 低频电磁场 晶粒细化 显微偏析 

分 类 号：TG249.7[金属学及工艺—铸造]