难混溶合金粉末中核/壳结构形成过程的可视化模拟与观测研究  

Visualized simulation and observational study on core/shell structure in immiscible alloy powders

作　　者：李梅 师晟祺 秦丽霞 彭银利 周先辉[1] LI Mei;SHI Shengqi;QIN Lixia;PENG Yinli;ZHOU Xianhui(School of Intelligent Manufacturing,Nanyang Institute of Technology,Nanyang 473004,China;Engineering Research Center of Additive Manufacturing Aeronautical Materials of Henan Province,Nanyang 473004,China)

机构地区：[1]南阳理工学院智能制造学院,河南南阳473004 [2]河南省增材制造航空材料工程研究中心,河南南阳473004

出　　处：《粉末冶金工业》2023年第5期69-73,112,共6页Powder Metallurgy Industry

基　　金：国家自然科学基金资助项目(52201044);河南省自然科学基金资助项目(212300410213);南阳市科技攻关资助项目(KJGG025);河南省大学生创新创业训练计划资助项目(202211653009)。

摘　　要：采用自制热台建立了环形温度梯度场,利用丁二腈-水(SCN-H_(2)O)溶液开展了原位相分离观测实验,“模拟”了微重力条件下难混溶合金粉末中核/壳结构形貌的演化过程。结果表明:第二相(L_(2))微球在向试样中心迁移过程中尺寸不断变化。首先,初始L_(2)相在两相区内因碰撞而尺寸变大,但变化不明显;其次,部分L_(2)相在超过双节点温度位置进入单相区后,尺寸减小;最后,随着试样温度降低,L_(2)相因剧烈碰撞而尺寸急速增大,形成核结构。此外,核是由尺寸较大的L_(2)相微球经多次碰撞后在试样中心凝固而形成的。An annular temperature gradient field was established by a self-made hot stage,and in-situ observation on the phase separation using SCN-H2O solution was performed to“simulate”the evolutionary procedure of the core/shell structure forming in immiscible alloy powders under microgravity conditions.The results show that the size of the second phase(L_(2))microspheres keeps changing during the migration to the specimen center.Firstly,the initial L_(2)phase becomes larger in the two-phase region due to collisions,but it is not obvious.Secondly,the size decreases after L_(2)phases exceed the binodal-temperature position and enter the single-phase region.Finally,with the decreasing temperature of specimen,the size of L_(2)phase increases rapidly due to fierce collisions and forms a core structure.In addition,the core structure is formed by the L_(2)phase microspheres experiencing multiple collisions in the center of the specimen.

关 键 词：核/壳结构 L_(2) 相分离 难混溶 原位观测 

分 类 号：TF124[冶金工程—粉末冶金]