中国物理B ›› 2014, Vol. 23 ›› Issue (12): 124702-124702.doi: 10.1088/1674-1056/23/12/124702

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Orientation-dependent morphological stability of grain boundary groove

王理林a b, 林鑫b, 王志军b, 黄卫东b   

  1. a School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China;
    b State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China
  • 收稿日期:2014-04-14 修回日期:2014-05-19 出版日期:2014-12-15 发布日期:2014-12-15
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant No. 51271213), the National Basic Research Program of China (Grant No. 2011CB610402), China Postdoctoral Science Foundation (Grant No. 2013M542384), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20116102110016).

Orientation-dependent morphological stability of grain boundary groove

Wang Li-Lin (王理林)a b, Lin Xin (林鑫)b, Wang Zhi-Jun (王志军)b, Huang Wei-Dong (黄卫东)b   

  1. a School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China;
    b State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China
  • Received:2014-04-14 Revised:2014-05-19 Online:2014-12-15 Published:2014-12-15
  • Contact: Lin Xin E-mail:xlin@nwpu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant No. 51271213), the National Basic Research Program of China (Grant No. 2011CB610402), China Postdoctoral Science Foundation (Grant No. 2013M542384), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20116102110016).

摘要:

Crystal orientation influences the morphological stability of solid–liquid interface during directional solidification of alloy, resulting in the variation of solidified microstructure. In this paper, the morphological evolution near grain boundary grooves (GBGs) with different crystal orientations in a dilute succinonitrile alloy under low temperature gradient and interface velocity is observed in situ. Under experimental conditions, the macroscopic solid–liquid interface is planar and keeps stable, while in GBGs there emerge protrusion and undulation. It is found that the morphological stability of GBG is dependent on crystal orientation. Specifically, for succinonitrile with a body-centered cubic crystal structure, GBGs around the <100> crystal orientation keep stable, while those apart from the <100> crystal orientation become unstable under the same conditions. So it is concluded that <100> crystal orientation favors the morphological stability of GBG.

关键词: morphological instability, grain boundaries, crystal orientation, solidification

Abstract:

Crystal orientation influences the morphological stability of solid–liquid interface during directional solidification of alloy, resulting in the variation of solidified microstructure. In this paper, the morphological evolution near grain boundary grooves (GBGs) with different crystal orientations in a dilute succinonitrile alloy under low temperature gradient and interface velocity is observed in situ. Under experimental conditions, the macroscopic solid–liquid interface is planar and keeps stable, while in GBGs there emerge protrusion and undulation. It is found that the morphological stability of GBG is dependent on crystal orientation. Specifically, for succinonitrile with a body-centered cubic crystal structure, GBGs around the <100> crystal orientation keep stable, while those apart from the <100> crystal orientation become unstable under the same conditions. So it is concluded that <100> crystal orientation favors the morphological stability of GBG.

Key words: morphological instability, grain boundaries, crystal orientation, solidification

中图分类号:  (Morphological instability; phase changes)

  • 47.20.Hw
61.72.Mm (Grain and twin boundaries) 81.10.Aj (Theory and models of crystal growth; physics and chemistry of crystal growth, crystal morphology, and orientation) 81.30.Fb (Solidification)