三维大体积金属材料电磁悬浮过程的精准调控

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.