Creep Behavior and Microstructure Evolution of Sand-Cast Mg-4Y-2.3Nd-1Gd-0.6Zr Alloy Crept at 523-573 K

CORC > 金属研究所 > 中国科学院金属研究所

	Creep Behavior and Microstructure Evolution of Sand-Cast Mg-4Y-2.3Nd-1Gd-0.6Zr Alloy Crept at 523-573 K
	Kang, Y. H. ; Yan, H. ; Chen, R. S.
刊名	JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
	2017
卷号	33 期号:1 页码:79-89
关键词	WE43 alloy Creep PFZs Precipitate Fracture
ISSN号	1005-0302
通讯作者	Yan, H ; Chen, RS (reprint author), Chinese Acad Sci, Inst Met Res, Grp Magnesium Alloys & Their Applicat, Shenyang 110016, Peoples R China.
中文摘要	High temperature tensile-creep behavior of Mg-4Y - 2.3Nd - 1Gd - 0.6Zr (wt%, WE43(T6)) alloy at 523-573 K was investigated. The creep stress exponent is equal to 4.6, suggesting the underlying dislocation creep mechanism. The activation energy is (199 +/- 23) kJ/mol, which is higher than that for sel-fdiffusion in Mg and is believed to be associated with precipitates coarsening or cross slip. The creep mechanism is further suggested to be dislocation climb at 523 K, while a cross slip at 573 K is possible. The metastable beta' and beta(1) phases in the WE43(T6) alloy were relatively thermal stable at 523 K and could be effective to hinder the dislocation climb, which contributed to its excellent creep resistance. However, at 573 K it readily transforms into equilibrium beta(e) phase and coarsens within two hours, thereby causing a decrease of creep resistance. In addition, precipitate free zones approximately normal to applied stress direction (directional PFZs) developed during the creep deformation, especially at 573 K. Those zones became preferential sites to nucleate, extend and connect microcracks and cavities, which lead to the intergranular creep fracture. Improving the thermal stability of precipitates or introducing thermally stable fine plate-shaped precipitates on the basal planes of Mg matrix could enhance the high temperature creep resistance. Copyright (C) 2017, The editorial office of Journal of Materials Science & Technology. Published by Elsevier Limited.
学科主题	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
收录类别	SCI
资助信息	National Basic Research Program of China [2013CB632202, 51531002]; National Natural Science Foundation of China [51301173]
语种	英语
公开日期	2017-08-17
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/78362]
专题	金属研究所_中国科学院金属研究所
推荐引用方式 GB/T 7714	Kang, Y. H.,Yan, H.,Chen, R. S.. Creep Behavior and Microstructure Evolution of Sand-Cast Mg-4Y-2.3Nd-1Gd-0.6Zr Alloy Crept at 523-573 K[J]. JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,2017,33(1):79-89.
APA	Kang, Y. H.,Yan, H.,&Chen, R. S..(2017).Creep Behavior and Microstructure Evolution of Sand-Cast Mg-4Y-2.3Nd-1Gd-0.6Zr Alloy Crept at 523-573 K.JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,33(1),79-89.
MLA	Kang, Y. H.,et al."Creep Behavior and Microstructure Evolution of Sand-Cast Mg-4Y-2.3Nd-1Gd-0.6Zr Alloy Crept at 523-573 K".JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY 33.1(2017):79-89.