Dislocation motion during high-temperature low-stress creep in Ru-free and Ru-containing single-crystal superalloys

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	Dislocation motion during high-temperature low-stress creep in Ru-free and Ru-containing single-crystal superalloys
	X. G.; Liu Wang, J. L.; Jin, T.; Sun, X. F.; Hu, Z. Q.; Do, J. H.; Choi, B. G.; Kim, I. S.; Jo, C. Y.
	2015
发表期刊	Materials & Design
ISSN	0261-3069
卷号	67 页码:543-551
摘要	Creep deformation of the two experimental single crystal superalloys at high-temperature low-stress (1140 degrees C/137 MPa) has been analyzed through transmission electron microscopy. Emphasis is placed on elucidating the dependence of dislocation motion on microstructural evolution. The detailed analysis demonstrated that the stacking fault energy of the c matrix significantly decreased with the addition of Ruthenium (Ru). The stacking faults presenting in the gamma matrix after heat treatment has been rarely reported previously. During the primary creep stage, the dislocations can easily cross-slip on the different {111} planes in the horizontal matrix and leave 60 degrees dislocation loops on the (001) gamma/gamma' interfacial plane. Furthermore, calculations demonstrated that it is difficult for the slipping dislocations to bow into the vertical gamma matrix channel. In the early stages of steady state creep, the interfacial dislocations reoriented slowly from the [110] slipping direction to the [100] well misfit stress relief direction. On the other hand, few dislocations shearing into the rafted gamma' phase have been observed. In fact, during the middle stages of the steady state creep, although perfect dislocation networks have formed, some dislocations shearing into the gamma' phase have also been observed. In addition, the a [010] type superdislocations (some with non-compact core) have also been observed in the two experimental alloys. At last, the Ru-containing alloy possesses more negative lattice misfit, denser gamma/gamma' interfacial dislocation networks and higher microstructural stability, thus can maintain a minimum creep rate in the steady state stage and have a longer creep life. (C) 2014 Elsevier Ltd. All rights reserved.
部门归属	[wang, x. g. ; liu, j. l. ; jin, t. ; sun, x. f. ; hu, z. q.] chinese acad sci, inst met res, superalloys div, shenyang 110016, peoples r china. [do, j. h. ; choi, b. g. ; kim, i. s. ; jo, c. y.] korea inst mat sci, high temp mat res grp, chang won 641831, gyeongnam, south korea. ; jin, t (reprint author), chinese acad sci, inst met res, superalloys div, 72 wenhua rd, shenyang 110016, peoples r china. ; tjin@imr.ac.cn
关键词	Ni-base Single Crystal Superalloy Creep Behavior Dislocation Structure Transmission Electron Microscopy Nickel-base Superalloys Gamma'-volume Fraction Internal-stresses Phase-stability Lattice Misfit Evolution Additions Behavior Microstructure Deformation
URL	查看原文
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/73965
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	X. G.,Liu Wang, J. L.,Jin, T.,et al. Dislocation motion during high-temperature low-stress creep in Ru-free and Ru-containing single-crystal superalloys[J]. Materials & Design,2015,67:543-551.
APA	X. G..,Liu Wang, J. L..,Jin, T..,Sun, X. F..,Hu, Z. Q..,...&Jo, C. Y..(2015).Dislocation motion during high-temperature low-stress creep in Ru-free and Ru-containing single-crystal superalloys.Materials & Design,67,543-551.
MLA	X. G.,et al."Dislocation motion during high-temperature low-stress creep in Ru-free and Ru-containing single-crystal superalloys".Materials & Design 67(2015):543-551.