不同电磁场对亚快速凝固下高镁5059铝合金铸轧板显微组织和力学性能的影响  

Effect of different electromagnetic fields on microstructure and mechanical properties of sub-rapid solidification-processed high Mg 5059 alloy during twin-roll casting

作　　者：付金禹 张敬宇 许久健 余创 张焘 许光明[1] 李勇[2] 王昭东[2] FU Jin-yu;ZHANG Jing-yu;XU Jiu-jian;YU Chuang;ZHANG Tao;XU Guang-ming;LI Yong;WANG Zhao-dong(Key Laboratory of Electromagnetic Processing of Materials,Ministry of Education,Northeastern University,Shenyang 110819,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学材料电磁过程研究教育部重点实验室,沈阳110819 [2]东北大学轧制技术及连轧自动化国家重点实验室,沈阳110819

出　　处：《中国有色金属学报》2023年第8期2456-2470,共15页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51790485);南宁市科技重大专项项目(20201041)。

摘　　要：通过金相显微镜(OM)、扫描电子显微镜(SEM)、电子背散射衍射(EBSD)、差示扫描量热法(DSC)和拉伸实验等表征方法,研究了不同外场对高镁5059铝合金铸轧板微观组织和力学性能的影响。结果表明:当不同外场应用到铸轧实验中,中心偏析和微观偏析缺陷显著消失,非平衡共晶相的数量呈现明显的减少趋势。此外,铸轧板芯部区域的晶粒尺寸和纵横比也同样呈现出下降趋势,其中,电磁振荡场的作用效果最为显著。在电磁振荡场中,铸轧区内的熔体受到电磁搅拌力,导致铸轧区内枝晶尖端的溶质浓度梯度显著降低,沿铸轧板厚度方向的温度场逐渐趋于均匀,合金元素的固溶度显著提高。最终,高镁5059合金铸轧板的综合力学性能大幅度提高。The effects of different external fields on the microstructure and mechanical properties of twin-roll casting(TRC)high Mg 5059 Al alloy sheets were investigated in detail by metallographic microscopy(OM),scanning electron microscopy(SEM),electron back-scatter diffractometry(EBSD),differential scanning calorimetry(DSC)and tensile testing.The results show that,when different external fields are applied,the central segregation defects and micro-segregation defects disappear significantly,and the number of non-equilibrium eutectic phases exhibits a reduction trend.Furthermore,the size and aspect ratio of grain size in the central area also show a downward trend,particularly,the evolution effect of electromagnetic oscillation field is the most significant.In the electromagnetic oscillation field,the melt in the cast-rolling zone is subjected to the electromagnetic stirring force,resulting in a significant decrease in the solute concentration gradient at the tip of the dendrites,and the temperature gradient along the thickness direction of cast-rolled sheet tends to be uniform as well as the solid solubility of the alloy is greatly improved.Eventually,the excellent comprehensive mechanical properties of the high Mg 5059 alloy sheet are enhanced.

关 键 词：5059铝合金 双辊铸轧 电磁振荡场 偏析缺陷 显微组织 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]