Inhibition of Cusp magnetic field on stray-crystal formation in platform region during directionally solidified single-crystal superalloy  

作　　者：Weili Ren Tao Zhou Xiaotan Yuan Ming Jian Congjiang Zhang Biao Ding Jianchao Peng Tianxiang Zheng Yunbo Zhong 

机构地区：[1]State Key Laboratory of Advanced Special Steel,College of Materials Science and Engineering,Shanghai University,Shanghai 200444,China [2]China National South Aviation Industry Co.,Ltd,Zhuzhou 412000,China [3]Laboratory for Microstructures,Shanghai University,Shanghai 200444,China

出　　处：《Journal of Materials Science & Technology》2022年第11期183-194,共12页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No.51871142);the Independent Research and Development Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University (No.SKLASS 2020-Z04);the Science and Technology Commission of Shanghai Municipality (No.19DZ2270200)。

摘　　要：The stray crystal in the platform region is one of the common main defects in single-crystal superalloy blades. The simple and effective method to eliminate this defect is urgent to be explored. This work found that the Cusp magnetic field can effectively inhibit the stray-crystal formation in the platform. The tendency of stray-crystal formation decreases as the magnetic-field strength increases at a certain withdrawal rate and temperature-gradient. The suppressing effect decreases as the withdrawal rate or the temperature-gradient increases. Finally, the inhibiting mechanism on the stray-crystal formation from the Cusp magnetic field is proposed based on the experiments and the numerical simulation. The magneticfield application strengthens the flow velocity and changes the flow structure near the liquid-solid interface, and further reduces the radial temperature difference. Accordingly, the secondary dendrites in the heat-conduction undercooled zone expands towards the corner in a faster speed, which reduces the stray-crystal formation in the platform corner. This study provides an effective and simple method for decreasing the stray-crystal formation during the preparation of single-crystal with platform region.

关 键 词：Single-crystal superalloy Cusp magnetic field Stray crystals Platform region 

分 类 号：TG132.3[一般工业技术—材料科学与工程]