α-Al磁性对强磁场下Al-Cu亚共晶合金定向凝固组织的影响  

Influence of Magnetism of α-Al on Unidirectional Solidification Structure of Al-Cu Hypoeutectic Alloys in a Strong Magnetic Field

作　　者：刘钱[1] 任忠鸣[1] 钟华[1] 李传军[1] 余建波[1] 

机构地区：[1]上海大学上海市现代冶金和材料制备重点实验室,上海200444

出　　处：《上海大学学报（自然科学版）》2014年第4期472-479,共8页Journal of Shanghai University:Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)资助项目(2011CB610404);上海市科委重点资助项目(13521101102)

摘　　要：以Al-Cu亚共晶合金为研究对象,考察了α-Al单晶磁各向异性对稳恒强磁场下定向凝固枝晶组织生长行为的影响.实验测定了α-Al单晶不同晶向的磁化率.结果表明:Al-Cu单晶中的磁化现象表现出明显的方向性;难磁化轴为晶体学位向<111>方向,即磁化率最小;易磁化轴为晶体学位向<311>或<310>方向,即磁化率最大;磁化率随Cu原子数量的增加而降低;[111]晶向族中4个晶向的磁化率不再一致.对于Al-0.85%Cu合金,当生长速度为50μm/s时,在无磁场情况下其定向凝固枝晶主干沿凝固方向排列;当施加6 T纵向强磁场时,枝晶主干偏离凝固方向成一定夹角排列,这一现象可能是由α-Al磁晶的各向异性所致.This paper studies the effect of magnetic anisotropy of α-Al single crystal on the dendritic morphology in AI-Cu hypoeutectic Mloy under a static high magnetic field during directional solidification. Magnetic susceptibility of α-Al single crystal slices with different crystal orientations are measured with the Faraday method. The results shows that the anisotropic and asymmetric magnetic property of the crystal cell of α-Al containing Cu. The 〈111〉-crystal direction is a hard magnetization direction while 〈311〉 or 〈310〉-crystal direction is an easy magnetization direction. Magnetic susceptibility decreases with increase of Cu content in α-Al. In addition, magnetic susceptibilities of the four crystal orientations among [111] are different. Besides, applying a 6 T longitudinal high magnetic field, the α-Al dendrite deviates from the heat flow direction, which is parallel to the solidification direction without a magnetic field at a growth speed of 50 αm/s.This phenomenon may be attributed to the crystal magnetic anisotropy energy of α-Al.

关 键 词：磁晶各向异性 AL-CU合金 定向凝固 枝晶形貌 

分 类 号：TG146.2[一般工业技术—材料科学与工程]