Three dimensional dendritic morphology and orientation transition induced by high static magnetic field in directionally solidified Al-10wt.%Zn alloy  

作　　者：Sansan Shuai Xin Lin Yuanhao Dong Long Hou Hanlin Liao Jiang Wang Zhongming Ren 

机构地区：[1]State Key Laboratory of Advanced Special Steel,School of Materials Science and Engineering,Shanghai University,Shanghai 200444, China [2]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072, China [3]Université de Technologie de Belfort-Montbéliard,LERMPS Site de Sévenans,90010 Belfort Cedex, France

出　　处：《Journal of Materials Science & Technology》2019年第8期1587-1592,共6页材料科学技术（英文版）

基　　金：financially supported by National Natural Science Foundation of China (Grant Nos. 51690162, 51604171 and 51701112);China Postdoctoral Science Foundation (Grant Nos. 2017T100291 and 2017M611530);Shanghai Municipal Science and Technology Commission (No. 17JC1400602);open funding of State Key Laboratory of Solidification Processing in NWPU (SKLSP201602 and SKLSP201706)

摘　　要：Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back-scattered Diffraction(EBSD) and X-ray Diffraction(XRD). The application of high static axial magnetic field(5T) during directional solidification was found to destabilize the solid/liquid interface and cause the growth direction of dendrite deviate from thermal gradient, leading to irregular solid/liquid interfacial shape and cellular to dendritic morphology transition. The thermoelectric magnetic convection(TEMC) caused by the interaction of thermoelectric effect and magnetic field was supposed to be responsible for the transition. In addition, the EBSD and XRD results confirm that the preferred growth direction of α-Al was found to transform from the traditionally expected <100> to<110>. The dendrite orientation transition(DOT) in Al-10 wt.%Zn alloy can be attributed to the effect of applied magnetic field on the anisotropy of crystal during solidification. The result indicates the potential application of high static magnetic field in altering the morphology and preferred growth direction of dendrite during directional solidification.Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back-scattered Diffraction(EBSD) and X-ray Diffraction(XRD). The application of high static axial magnetic field(5T) during directional solidification was found to destabilize the solid/liquid interface and cause the growth direction of dendrite deviate from thermal gradient, leading to irregular solid/liquid interfacial shape and cellular to dendritic morphology transition. The thermoelectric magnetic convection(TEMC) caused by the interaction of thermoelectric effect and magnetic field was supposed to be responsible for the transition. In addition, the EBSD and XRD results confirm that the preferred growth direction of α-Al was found to transform from the traditionally expected <100> to<110>. The dendrite orientation transition(DOT) in Al-10 wt.%Zn alloy can be attributed to the effect of applied magnetic field on the anisotropy of crystal during solidification. The result indicates the potential application of high static magnetic field in altering the morphology and preferred growth direction of dendrite during directional solidification.

关 键 词：AL-ZN ALLOY HIGH static magnetic field Three-dimensional DENDRITE morphology DENDRITE ORIENTATION TRANSITION X-ray computed tomography 

分 类 号：TG[金属学及工艺]