合金凝固过程中，初晶相的生长方式决定了自身形态和后续相的生长行为，进而显著影响合金的组织及性能。利用外场对初晶相的生长方式进行控制具有重要理论意义和应用价值。本项目将透明有机物凝固过程的在线观察、二元合金凝固过程中温度的在线测量和组织的离线检测相结合，研究强磁场下合金凝固过程中初晶相生长方式的变化。通过透明有机物和二元合金的自由凝固、定向凝固和淬火实验，借助晶界凹槽形态测定、原位观察和组织分析等手段，研究强磁场对合金凝固过程中初晶相生长的固/液界面能、溶质分布、过冷度等参数的影响规律和作用机制；考察上述参数在强磁场下的变化规律对初晶相生长方式的作用效果及竞争关系；阐明强磁场对凝固过程中初晶相生长方式选择的影响规律和物理机制；提出利用强磁场控制初晶相生长进而控制凝固组织的新思路。研究结果将完善强磁场下的晶体生长理论，促进强磁场材料科学研究的发展，为外场下材料的组织控制提供理论指导和实验依据。

During the solidification process of alloys, the morphology of the solid/liquid interface of the primary phase can alter its growth morphology and the growth behavior of the following phases, and then obviously affect the solidification microstructure and properties of the alloys. It is of great importance to control the morphology of the solid/liquid interface of the primary phase by using external fields. Combining the in situ observation of a transparent alloy and microstructure analysis of binary alloys, the effect of high magnetic fields on the morphology of the solid/liquid interface of the primary phase will be studied. The solidification, directional solidification, and quenching experiments of the transparent alloy and binary alloys in high magnetic fields will be carried out. With the aid of the measurement of grain boundary groove shapes, in situ observation, on-line measurement, and microstructure analysis, the effects of high magnetic fields on the interfacial energy, partition coefficient, and undercooling about the primary phase growth during solidification process of alloys and their mechanism will be investigated. The influences of above effects on the solid/liquid interface morphology of the primary phase and the relation between these influences will be clarified. The effects of high magnetic fields on the morphology of the solid/liquid interface of the primary phase during solidification process of alloys and the mechanism about these effects will be clarified. A novel method for in situ control of the solidification process of alloys by magnetic field will be proposed. The results of this project will enrich the fundamental theory of crystal growth in high magnetic fields, promote the research on the materials science in high magnetic fields, and then guide the control of the microstructure of materials by external fields.