On the mechanism of crack propagation resistance of fully lamellar TiAl alloy

doi:10.1016/j.msea.2006.01.089

CORC > 兰州理工大学 > 兰州理工大学

	On the mechanism of crack propagation resistance of fully lamellar TiAl alloy
	Cao, R ; Yao, HJ ; Chen, JH ; Zhang, J
刊名	MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
	2006-03-25
卷号	420 期号:1-2 页码:122-134
关键词	TiAl alloy fracture behavior crack propagation resistance toughening mechanism
ISSN号	0921-5093
DOI	10.1016/j.msea.2006.01.089
英文摘要	The study was done using notched two-colony thick tensile specimens of a directionally solidified cast fully lamellar TiAl alloy. In-situ observations of fracture processes in scanning electron microscope (SEM) were combined with section-to-section related observations of fracture surfaces to investigate the crack growth process. Finite element method (FEM) calculations are carried out to evaluate the stresses for propagating cracks. The results reveal that: ( 1) the reason why enhancement of applied load is required to propagate the main crack, was attributed to that the main crack observed at the surface did not extend all the way through the specimen's thickness thus the stress field was still controlled by the notch, in which a definite stress required for extending a crack tip should be kept by increasing the applied load. (2) Crack propagation resistance is enhanced at colony boundaries, only when a change occurs from an inter-lamellar propagation to a trans-lamellar propagation (3) Ligament bridging toughening phenomena can be integrated into aforementioned mechanism. As a whole the processes of new crack nucleation with bridging ligament formation decreases the crack propagation resistance rather than increasing it. (4) In case the majority of microcracks are surface cracks, the effect of microcrack shielding is not obvious. (c) 2006 Elsevier B.V. All rights reserved.
WOS研究方向	Science & Technology - Other Topics ; Materials Science ; Metallurgy & Metallurgical Engineering
语种	英语
出版者	ELSEVIER SCIENCE SA
WOS记录号	WOS:000236952100017
状态	已发表
内容类型	期刊论文
源URL	[http://119.78.100.223/handle/2XXMBERH/35702]
专题	兰州理工大学
通讯作者	Chen, JH
作者单位	1.Gansu Univ Technol, Lanzhou Univ Technol, State Key Lab Adv Nonferrous Met Mat, Coll Mat Sci & Engn, Lanzhou 730050, Gansu, Peoples R China 2.Cent Iron & Steel Res Inst, Beijing 100081, Peoples R China
推荐引用方式 GB/T 7714	Cao, R,Yao, HJ,Chen, JH,et al. On the mechanism of crack propagation resistance of fully lamellar TiAl alloy[J]. MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING,2006,420(1-2):122-134.
APA	Cao, R,Yao, HJ,Chen, JH,&Zhang, J.(2006).On the mechanism of crack propagation resistance of fully lamellar TiAl alloy.MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING,420(1-2),122-134.
MLA	Cao, R,et al."On the mechanism of crack propagation resistance of fully lamellar TiAl alloy".MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 420.1-2(2006):122-134.