Crack propagation mechanism of gamma-TiAl alloy with pre-existing twin boundary

doi:10.1007/s11431-017-9307-5

CORC > 兰州理工大学 > 兰州理工大学 > 机电工程学院

	Crack propagation mechanism of gamma-TiAl alloy with pre-existing twin boundary
	Cao Hui 1,2,3; Rui ZhiYuan 1,2,3; Chen WenKe 1,2,3; Feng RuiCheng 1,2,3; Yan ChangFeng 1,2,3
刊名	SCIENCE CHINA-TECHNOLOGICAL SCIENCES
	2019-09
卷号	62 期号:9 页码:1605-1615
关键词	crack propagation gamma-TiAl twin boundary molecular dynamics deformation mechanism
ISSN号	1674-7321
DOI	10.1007/s11431-017-9307-5
英文摘要	The deformation and failure mechanisms of gamma-TiAl alloy with pre-existing crack and twin boundary are investigated by using molecular dynamics simulation. The effects of the crack position on the deformation and failure mechanisms of gamma-TiAl specimen are analysed through the snapshots of crack propagation, microstructure of crack tip and stress-strain curves. The simulation results show that the dislocation motion is impeded, the good ductility can be maintained and the strength would be improved simultaneously by the twin boundary. The microstructure evolution of crack tip would change with crack positions. Essentially, the deformation behaviour mainly results from the reaction of dislocation-dislocation, dislocation-twin and twin-twin. Besides, the hierarchical twin is a main plastic deformation mechanism leading to strength of gamma-TiAl specimen enhancement with non-compromising ductility and strain hardening. Based on stress-strain curves, it can be concluded that the yield strength varies with crack positions. They are the determinant factors for variation of the yield strength with different crack positions such as dislocation behaviour, stacking fault and hierarchical twin. The ductile-brittle transition associated with the dislocation motion and the decohesion failure of crack tip atom can be observed from the lower boundary crack and the center crack models. The crack propagation caused by the coalescent of the void and the crack tip is the main failure mechanism of gamma-TiAl specimen. In addition, the results reveal that the mechanism of crack propagation would be influenced by pre-existing twin boundary which can prevent the crack propagation and improve the fracture toughness.
资助项目	National Natural Science Fundation of China[51665030][51865027] ; Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China[IRT_15R30]
WOS研究方向	Engineering ; Materials Science
语种	英语
出版者	SCIENCE PRESS
WOS记录号	WOS:000484901200013
状态	已发表
内容类型	期刊论文
源URL	[http://119.78.100.223/handle/2XXMBERH/31583]
专题	机电工程学院土木工程学院省部共建有色金属先进加工与再利用国家重点实验室
通讯作者	Rui ZhiYuan
作者单位	1.Lanzhou Univ Technol, Minist Educ, Engn Res Ctr Nonferrous Met New Equipment, Lanzhou 730050, Gansu, Peoples R China 2.Lanzhou Univ Technol, Sch Mech & Elect Engn, Lanzhou 730050, Gansu, Peoples R China 3.Lanzhou Univ Technol, State Key Lab Adv Proc & Recycling Nonferrous Met, Lanzhou 730050, Gansu, Peoples R China
推荐引用方式 GB/T 7714	Cao Hui,Rui ZhiYuan,Chen WenKe,et al. Crack propagation mechanism of gamma-TiAl alloy with pre-existing twin boundary[J]. SCIENCE CHINA-TECHNOLOGICAL SCIENCES,2019,62(9):1605-1615.
APA	Cao Hui,Rui ZhiYuan,Chen WenKe,Feng RuiCheng,&Yan ChangFeng.(2019).Crack propagation mechanism of gamma-TiAl alloy with pre-existing twin boundary.SCIENCE CHINA-TECHNOLOGICAL SCIENCES,62(9),1605-1615.
MLA	Cao Hui,et al."Crack propagation mechanism of gamma-TiAl alloy with pre-existing twin boundary".SCIENCE CHINA-TECHNOLOGICAL SCIENCES 62.9(2019):1605-1615.