基于磁场作用下的金属凝固研究现状

Research Status of Metal Solidification Based on Magnetic Field

利用磁场辅助金属凝固,不仅可以细化晶粒、改善凝固组织的力学性能,同时由于磁场和熔融态金属是非直接接触,还可以避免缺陷的引入,进而已成为研究热点。针对磁场作用下的金属熔体形核和晶核生长特点,对金属凝固过程进行深入分析,从磁场对金属凝固的影响原理和仪器设备两个方面进行总结,综述磁场作用下金属凝固的研究进展;分别从铁磁性、顺磁性、抗磁性三种磁性金属在磁场作用下试验研究进行梳理分析。结果表明:磁场引发的洛伦兹力、热电磁力、磁转矩及磁取向等作用通过影响金属熔体的形核和晶核生长,最终改善凝固组织性能;磁场设备利用永磁铁或者电磁铁产生磁场环境;三种磁性金属在磁场环境下凝固后的性能改善体现在力学性能、导电性能、磁性能等方面。最后归纳磁场辅助金属凝固过程中所存在的问题,并展望未来的发展趋势。

The use of magnetic field to assist metal solidification can not only refine the grains and improve the mechanical properties of the solidified structure, but also avoid the introduction of defects due to the non-direct contact between the magnetic field and the molten metal, which has become a research hotspot. Aiming at the characteristics of metal melt nucleation and crystal nucleation growth under the action of a magnetic field, an in-depth analysis of the metal solidification process is carried out. At the same time,combing and analyzing the experimental studies of ferromagnetic, paramagnetic and diamagnetic metals under the action of a magnetic field are carried out respectively. The results show that the Lorentz force, thermo-electromagnetic force, magnetic torque and magnetic orientation induced by the magnetic field affect the nucleation and nucleation growth of the metal melt, and finally improve the solidified microstructure and properties;the magnetic field equipment uses permanent magnets or electromagnets to generate Magnetic field environment;the performance improvement of the three magnetic metals after solidification in the magnetic field environment is reflected in mechanical properties, electrical conductivity, magnetic properties and so on. Finally, the problems existing in the magnetic field-assisted metal solidification process are summarized and the future development trend is prospected.