中文摘要：

采用强磁场复合交变电流方法细化Zn-20％Bi过偏晶合金的显微凝固组织，研究了磁感应强度、电磁振荡强度和交变电流频率对Zn-20％Bi过偏晶合金显微组织的影响。随着磁感应强度的增加，合金组织中第二富Bi相粒径逐渐得到细化；随着电磁振荡强度的增加，富Bi相尺寸先减小后增加；随着交变电流频率的增加，富Bi相尺寸也是先减小后增加，存在一个最佳频率。并解释说明了各因素的影响机制。

英文摘要：

Microstructure of Zn-20%Bi hypermonotectic alloy was refined through electromagnetic vibration produced by high magnetic field compound with alternative current （AC）.The effects of magnetic induction intensity,electromagnetic vibration and AC frequency on the microstructure of Zn-20%Bi hypermonotectic alloy were investigated.The results showed that increas-ing the intensity of magnetic induction is beneficial to the refinement of the second Bi-rich phase.We also found that the dimen-sion of Bi-rich phase decreased firstly and increased later with the increase of electromagnetic vibration and AC frequency.Both e-lectromagnetic vibration and AC frequency had an optimal value.The mechanisms of different factors are discussed.