Influence of the low voltage pulsed magnetic field on the columnar-to-equiaxed transition during directional solidification of superalloy K4169  

作　　者：Kuiliang Zhang Yingju Li Yuansheng Yang 

机构地区：[1]Institute of Metal Research,Chinese Academy of Sciences,Shenyang,110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Hefei,230026,China

出　　处：《Journal of Materials Science & Technology》2020年第13期9-17,共9页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.51674236);the Key Research and Development Program of Liaoning Province(2019JH2/10100009);the National Science and Technology Major Project(No.2017-VI-00-0073);the National Key Research and Development Program(No.2018YFA0702900).

摘　　要：The low voltage pulsed magnetic field(LVPMF)disrupts the columnar dendrite growth,and the columnarto-equiaxed transition(CET)occurs during the directional solidification of superalloy K4169.Within the pulse voltage ranging from 100Vto 200 V,a transition from columnar to equiaxed grain was observed,and the grain size decreased as the pulse voltage rised.As the pulse frequency increased,the CET occurred,and the grains were refined.However,the grains became coarse,and the solidification structure was columnar crystal again when frequency increased to 10 Hz.The LVPMF had an optimal frequency to promote CET.The LVPMF on the CET was affected by the withdrawal speed and increasing the withdrawal speed enhances the CET.The distribution of electromagnetic force and flow field in the melt under the LVPMF were modeled and simulated to reveal the CET mechanism.It is considered that the CET should be attributed to the coupling effects of magnetic vibration and melt convection induced by the LVPMF.

关 键 词：CET Low voltage pulsed magnetic field Simulation Directional solidification SUPERALLOY 

分 类 号：TG244.3[金属学及工艺—铸造] TG132.3[一般工业技术—材料科学与工程]