研究了在凝固过程中行波磁场对Cu-Ni-Si-Mg合金组织和性能的影响。结果表明，随着磁场电流强度的增加，在晶粒细化的同时，合金的组织形貌逐渐向等轴晶转变，树枝晶在磁场的作用下尺寸不断减小。磁场电流为90 A时晶粒细化效果最好，铸锭几乎全部由细小的等轴晶组成，晶粒尺寸降至(0.5±0.19) mm，相比于未加行波磁场的合金，晶粒细化了约94%。采用透射电子显微镜对显微组织进行观察，并对衍射花样进行标定，发现晶界处的析出相为δ-Ni2Si。在磁场电流为60 A的条件下，合金的拉伸性能最好，与未施加磁场的样品相比，屈服强度提高了41.8%，抗拉强度提高了12.9%，但合金的硬度不受行波磁场影响。本文通过行波磁场细化晶粒，为提高时效强化型铜合金的强度提供了一种可规模化生产的技术。

The microstructure and properties of Cu-Ni-Si-Mg alloys were studied by applying a travelling magnetic field during solidification. The results show that the microstructure of the alloy gradually changes to an equiaxed crystal shape, while the grains are refined with increasing magnetic field current, and the size of the dendrites decreases continuously under the action of a magnetic field. When the magnetic field current is 90 A, the grain size is the finest. The ingot is almost entirely composed of fine equiaxed crystals, and the grain size is reduced by approximately 94% to (0.5±0.19) mm compared to that of the alloy without the travelling magnetic field. The microstructure was observed by transmission electron microscope and the diffraction pattern was confirmed. The precipitated phase at the grain boundaries is δ-Ni2Si. Under the condition of a 60 A magnetic field current, the tensile strength of the alloy is the largest, the yield strength increases by 41.8%, and the tensile strength increases by 12.9%, while the hardness of the alloy is not affected by the travelling magnetic field. This paper describes the development of a scalable production technology for improving the strength of age-hardened Cu alloys by refining grains with a travelling magnetic field.