(1. 上海大學 材料科學與工程學院，上海 200444；
2. 上海大學 省部共建高品質(zhì)特殊鋼冶金與制備國家重點實驗室，上海 200444)
摘 要: 研究穩(wěn)恒強磁場對Cu-15Ni-8Sn合金凝固過程中微觀組織形貌、枝晶主干處成分偏析及顯微硬度的影響規(guī)律。結(jié)果表明：對比無磁場條件，2 T強磁場對Cu-15Ni-8Sn合金試樣微觀組織與枝晶主干處微觀偏析的影響并不大。但當磁感應強度提高至4~6 T時，試樣枝晶數(shù)量明顯減少，尺寸顯著粗化；且枝晶主干處Sn元素含量明顯下降，Ni元素含量則明顯升高。此外，強磁場的施加能顯著提高Cu-15Ni-8Sn合金枝晶主干的顯微硬度，對比無磁場條件，施加6 T強磁場時合金中枝晶主干處顯微硬度上升74.4%。強磁場對Cu-Ni-Sn合金微觀偏析及顯微硬度的影響主要與磁場在合金凝固過程中對Sn、Ni等元素擴散的影響有關(guān)。
關(guān)鍵字: Cu-15Ni-8Sn合金；縱向強磁場；微觀偏析；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
