(西北工业大学 应用物理系，西安 710072)
摘 要: 采用数值模拟方法建立单层和双层电磁感应线圈的仿真模型，分析线圈几何构型对空间磁场分布、金属球体表面的麦克斯韦应力张量分布和线圈悬浮性能的作用规律。选取Al和Ti两种金属作为实验对象，研究线圈匝数、金属质量与最小悬浮电流之间的本征关系。设计多种用于大体积金属无容器处理的电磁悬浮线圈，并实现直径10~50 mm的三种球状金属在空气中的悬浮加热。利用优化设计的线圈成功悬浮Al、Ti和Cu三种不同密度的典型金属，其中悬浮起质量高达807 g的纯铜。
关键字: 大体积金属材料；电磁线圈；悬浮力；优化设计
（Department of Applied Physics, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract:Containerless processing technique of bulk metals is of great importance not only in fundamental sciences, such as materials science and liquid physics, but also for the development of advanced materials. Due to the small size of levitated samples, novel materials research and its industrial application are seriously restricted. Therefore, a numerical model of single-layer coil and double-layer coil was established to analyze the effect of the coil structure on the distribution of magnetic field, the surface pressure and the levitation capability. Besides, the relationship among number of turns, metal mass and the minimum value of levitation current were investigated experimentally. Meanwhile, various electromagnetic levitation coils were designed to increase the levitation force, which were used to perform containerless processing of bulk metallic materials. Three kinds of spherical bulk metals are successfully levitated and heated by the designed coils, whose diameters range from 10 to 50 mm. Electromagnetic levitation of 807 g copper has been successfully achieved by greatly enhancing the levitation force through the optimized geometric structure of the coil.
Key words: bulk metallic materials; electromagnetic levitation coils; levitation force; optimization design
