Specific gravity segregation that occurs during the smelting process always leads to the low composition homogeneity and poor performance stability of the magnesium-rare earth(Mg-RE)alloys.In this study,the segregation behavior of Mg-Gd alloy was investigated by sampling from different locations in the ingot fabricated in a resistance furnace without a pouring process.The combined application of induction-heating and mechanical stirring with various speeds(0-130 r/min)was applied to promote the distribution homogeneity of Gd atoms.In the resistance-heating fabricated ingot,Gd content at the bottom section reaches 407％of that at the top.The coarse dendrites surrounded by the network-like eutectic structures are responsible for the brittle fracture with a poor elongation of 3.7％.By the com-bined employment of the induction heating and mechanical stirring with the speed of 87 r/min at 740℃for 40 s,the variation of the Gd content within the whole ingot can be reduced to be the minimum of 0.23 wt％.Corresponding formation and regulating models of segregation were also proposed.However,the cooling rate of the melt is reduced by the continuous increase of the stirring speed to 130 r/min,which results in the grain coarsening and lower homogeneity of the ingot.

Xin Tong;Guoqiang You;Fanjin Yao;Mahmoud Ebrahimi;Xinyue Deng;Shokouh Attarilar

College of Materials Science and Engineering,Chongqing University,Chongqing 400045,China;National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;National Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing 400044,China;Department of Mechanical Engineering,Faculty of Engineering,University of Maragheh,P.O.Box 55136-533,Maragheh,Iran;School of Materials Science and Engineering,Iran University of Science and Technology,Tehran,Iran

稀土学报（英文版）

[1]Xin Tong;Guoqiang You;Fanjin Yao;Mahmoud Ebrahimi;Xinyue Deng;Shokouh Attarilar-.Segregation behavior and its regulating process in as-cast magnesium alloy containing heavy rare earth)[J].稀土学报（英文版）,2022(08):1291-1304

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