Mechanism of primary Si and Fe-segregation for a hypereutectic 90 wt.%Si-Ti alloy melt in directional solidification via electromagnetism  

作　　者：Kui-song Zhu Li Cao Ying-tao Zhao Jun Wang Xiang-kui Cheng 

机构地区：[1]College of Vanadium and Titanium,Panzhihua University,Panzhihua 617000,Sichuan,China

出　　处：《Journal of Iron and Steel Research International》2023年第4期726-735,共10页

基　　金：the Sichuan Science and Technology Program(2021YJ0548);Panzhihua Science and Technology Project(2020CY-G-15);Research Project of Panzhihua University(2020ZD002);Project of Sichuan Key Laboratory for comprehensive utilization of vanadium and titanium resources(2019FTSZ06,2020FTSZ01).

摘　　要：The electromagnetic directional solidification(DS)phase separation experiments of high silicon 90 wt.%Si–Ti alloy were performed under various pulling-down speeds.The results showed that Si enriched layer,Si+TiSi_(2)-rich layer and Si–Ti–Fe alloy layer appeared successively in axial direction of ingot after electromagnetic DS of 90 wt.%Si–Ti alloy melt at different pulling-down speeds.Separation of primary Si and segregation mechanism of metal impurities(Fe)during the electromagnetic DS process were controlled by pulling-down speed of ingot and electromagnetic stirring.When pulling-down speed was 5μm/s,minimum thickness of the Si enriched layer was 29.4 mm,and the highest content of primary Si in this layer was 92.46 wt.%;meanwhile,the highest removal rate of Fe as metal impurity was 92.90%.The type of inclusions in the Si enriched layer is determined by Fe content of segregated Si enriched layer.When the pulling-down speed was 5μm/s,the inclusions in the Si enriched layer were TiSi_(2).Finally,when the pulling-down speed reached greater than 5μm/s,the inclusions in the Si enriched layer evolved into TiSi_(2)+τ_(5).

关 键 词：High silicon Si-Ti alloy Primary Si Electromagnetic directional solidification Si enriched layer Impurity segregation 

分 类 号：TG146[一般工业技术—材料科学与工程]