(1. 上海大学 材料科学与工程学院，上海 200444；
2. 上海大学 省部共建高品质特殊钢冶金与制备国家重点实验室，上海 200444)
摘 要: 研究稳恒强磁场对Cu-15Ni-8Sn合金凝固过程中微观组织形貌、枝晶主干处成分偏析及显微硬度的影响规律。结果表明：对比无磁场条件，2 T强磁场对Cu-15Ni-8Sn合金试样微观组织与枝晶主干处微观偏析的影响并不大。但当磁感应强度提高至4~6 T时，试样枝晶数量明显减少，尺寸显著粗化；且枝晶主干处Sn元素含量明显下降，Ni元素含量则明显升高。此外，强磁场的施加能显著提高Cu-15Ni-8Sn合金枝晶主干的显微硬度，对比无磁场条件，施加6 T强磁场时合金中枝晶主干处显微硬度上升74.4%。强磁场对Cu-Ni-Sn合金微观偏析及显微硬度的影响主要与磁场在合金凝固过程中对Sn、Ni等元素扩散的影响有关。
关键字: Cu-15Ni-8Sn合金；纵向强磁场；微观偏析；成分分布
（1. School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;
2. State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200444, China）
Abstract:The effect of static high magnetic field on the microstructure morphology, dendrite microsegregation and microhardness during the solidification of Cu-15Ni-8Sn alloy was studied. The results show that the 2 T high magnetic field has almost no effect on the microstructure or dendrite microsegregation of Cu-15Ni-8Sn alloy comparing with the condition of no magnetic field. While when the magnetic field increases to 4-6 T, the number of dendrites is significantly reduced, while the size of dendrites is significantly coarsened, and the content of Sn in the trunk of the dendrites is significantly reduced, while the content of Ni in the trunk of the dendrites is significantly increased. In addition, the application of high magnetic field can significantly increase the microhardness of dendrite trunk in Cu-15Ni-8Sn alloy. Comparing with the case without magnetic field, the magnetic field of 6 T increases the microhardness of dendrite trunk by 74.4%. The effect of static high magnetic field on the microsegregation and microhardness of Cu-Ni-Sn alloy is mainly related to the effect of magnetic field on the diffusion of Sn and Ni during solidification process.
Key words: Cu-15Ni-8Snalloy; high magnetic field; microsegregation; composition distribution
