(上海大学 材料科学与工程学院，上海 200072)
摘 要: 研究强磁场和交流电叠加对纯铝凝固组织的影响。结果表明：强磁场和交流电叠加对纯铝的凝固组织产生明显的细化作用，磁场强度一定时(10 T)，随电流强度增大，细化效果变好；电流强度一定时(10 A)，随着磁场强度的增大，晶粒细化程度先增强后略为减弱，其最佳值为6 T；液体金属在叠加场中受电磁振荡力和电磁粘滞力的共同作用，其合力随着磁场强度的增大先增加后减小，存在极值点，而晶粒细化与该合力直接相关。
关键字: 纯铝；强磁场；交流电；电磁力；细化
and alternative current on solidification structures of pure aluminum
（School of Material Science and Engineering, Shanghai University, Shanghai 200072, China）
Abstract:The refinement of solidified structure of pure aluminum by locally and simultaneously imposing a static magnetic field and an alternating current that generated a vibration in the melt was investigated. It is shown that the imposition refines the crystal grains greatly. The extent of grain refinement is increased with increase magnitude of alternating current. At a certain alternating current, the refinement is increased firstly with increasing magnetic field and then reaches the optimum value at 6 T. With further increase of the magnitude of magnetic field, the refining effect is diminished. Two forces arise from the magnetic field, one is the magnetic vibration force and the other is magnetic viscous force, and the refinement of grains is related to the resultant force from these forces.
Key words: aluminum; high magnetic field; AC current; electromagnetic vibration force; refinement
