Realizing the purification and grain refinement of Mg-Gd-Y alloy by one-step flux refining  

作　　者：Xin Tong Guohua Wu Ming Sun Qiman Wang Liang Zhang Wencai Liu 

机构地区：[1]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 [2]School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China

出　　处：《Journal of Materials Science & Technology》2024年第6期202-217,共16页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.U2037601 and 51821001);the Research Program of Joint Research Center of Advanced Spaceflight Technologies(No.USCAST2020-31).

摘　　要：In the conventional melt preparation of magnesium rare-earth(Mg-RE)alloys,the repeated heating/cooling process involved in grain refinement and flux refining usually prolongs the preparation period and aggravates melt oxidation.In this work,the purification and grain refinement of Mg-9Gd-3Y(GW93)alloy was simultaneously realized by one-step refining at 740℃ by using a self-developed compound flux.The results show that,only after holding for 10 min,the inclusion content of the alloy is reduced by 81%to 0.29%,while the grain size is reduced by 84%to 119μm.A physical model depicting the interactions between compound flux and alloy melt was proposed based on thermodynamic calculation and microstructure observation.The grain refinement mechanism has been analyzed by considering the presence of Zr particle(Zr_(p))and Zr solute(Zr_(s)).In addition,the generated RECl_(3) was found to be readily absorbed by the flux,decreasing the surface tension and promoting the purification efficacy of the flux,which plays an important role in the promoted elongation of the as-cast Mg-9Gd-3Y-0.5Zr(GW93K)alloy.This work presents a unique prospect in simplifying the melt preparation of Mg-RE alloy with a promoted quality.

关 键 词：Mg-Gd-Y-Zr alloy PURIFICATION Grain refinement Compound flux Settling behavior 

分 类 号：TG146.21[一般工业技术—材料科学与工程]