High-temperature failure mechanism and defect sensitivity of TC17 titanium alloy in high cycle fatigue

doi:10.1016/j.jmst.2022.01.010

CORC > 力学研究所 > 中国科学院力学研究所 > 非线性力学国家重点实验室

	High-temperature failure mechanism and defect sensitivity of TC17 titanium alloy in high cycle fatigue
	Li, Gen 2; Sun, Chengqi 1,2
刊名	JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
	2022-09-20
卷号	122 页码:128-140
关键词	TC17 titanium alloy High temperature Defect High cycle fatigue Oxygen-rich layer Rough area
ISSN号	1005-0302
DOI	10.1016/j.jmst.2022.01.010
通讯作者	Sun, Chengqi(scq@lnm.imech.ac.cn)
英文摘要	Crack initiation is an essential stage of fatigue process due to its direct effect on fatigue failure. However, for titanium alloys in high-temperature high cycle fatigue (HCF), the crack initiation mechanisms remain unclear and the understanding for the defect sensitivity is also lacking. In this study, a series of fatigue tests and multi-scale microstructure characterizations were conducted to explore the high-temperature failure mechanism, and the coupled effect of temperature and defect on TC17 titanium alloy in HCF. It was found that an oxygen-rich layer (ORL) was produced at specimen surface at elevated temperatures, and brittle fracture of ORL at surface played a critical role for surface crack initiation in HCF. Besides, internal crack initiation with nanograins at high temperatures was a novel finding for the titanium alloy. Based on energy dispersive spectroscopy, electron backscatter diffraction and transmission electron microscope characterizations, the competition between surface and internal crack initiations at high temperatures was related to ORL at surface and dislocation resistance in inner microstructure. The fatigue strengths of smooth specimens decreased at elevated temperatures due to the lower dislocation resistance. While the fatigue strengths of the specimens with defect were not very sensitive to the temperatures. Finally, a fatigue strength model considering the coupled effect of temperature and defect was proposed for TC17 titanium alloy. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
资助项目	National Natural Science Foundation of China[91860112] ; International Postdoctoral Exchange Fellowship Program (China)
WOS关键词	CRACK INITIATION ; ALUMINIDE ALLOY ; STRESS RATIO ; EARLY GROWTH ; BEHAVIOR ; TI-6AL-4V ; MICROSTRUCTURE ; TOLERANCE ; REGIMES
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
语种	英语
WOS记录号	WOS:000788133900003
资助机构	National Natural Science Foundation of China ; International Postdoctoral Exchange Fellowship Program (China)
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/88994]
专题	力学研究所_非线性力学国家重点实验室
通讯作者	Sun, Chengqi
作者单位	1.Univ Chinese Acad Sci, Sch Engn Sci, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Li, Gen,Sun, Chengqi. High-temperature failure mechanism and defect sensitivity of TC17 titanium alloy in high cycle fatigue[J]. JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,2022,122:128-140.
APA	Li, Gen,&Sun, Chengqi.(2022).High-temperature failure mechanism and defect sensitivity of TC17 titanium alloy in high cycle fatigue.JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,122,128-140.
MLA	Li, Gen,et al."High-temperature failure mechanism and defect sensitivity of TC17 titanium alloy in high cycle fatigue".JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY 122(2022):128-140.