Mechanism of cleavage fracture of HSLA steel

	Mechanism of cleavage fracture of HSLA steel
	Chen, J.H.; Wang, G.Z.
	2005
会议名称	11th International Conference on Fracture 2005, ICF11
会议录名称	11th International Conference on Fracture 2005, ICF11
卷号	6
页码	3968-3973
会议日期	March 20, 2005 - March 25, 2005
会议地点	Turin, Italy
出版者	International Congress on Fracture
摘要	Combined with the observations of configuration changes of pre-crack tips, fracture surfaces and finite element method (FEM) simulation and calculation, this paper suggests a new framework for cleavage mechanism of precracked specimens of HSLA steel at -110°C. This model includes three criteria i.e. Εp ≥ Εpc, for initiating a crack nucleus; σm/σe≥Tc, for preventing the crack nucleus from blunting; σyy≥σf, for propagating the crack nucleus into matrix grain and a supplementing requirement that a short crack initiates, extends and is blunted at the precrack tip. As long as the fatigue pre-crack is only blunted, in its vicinity a region, where the accumulated strain is sufficient to nucleate a crack and a region, where the stress (triaxiality) is sufficient to propagate, a crack nucleus is separated by a distance. The nucleated crack cannot be propagated and the cleavage fracture cannot be triggered. A short crack produced at the fully blunted fatigue pre-crack will change the distributions of strain, stress and triaxiality and specially their relative locations ahead of the pre-crack. While the strain retains, the stress (triaxiality) is rebuilt. The initiated, extended and then blunted short crack makes a tip configuration, which is much sharper than that of the fully blunted original pre-crack tip. The sharpened crack tip configuration re-builds a 'sharper' distribution of stress (triaxiality) and make above two regions closer. Finally the two regions overlap each other and a cleavage crack can be initiated and propagated at a distance ahead of the blunted fatigue pre-crack.
关键词	Crack propagation Crack tips High-strength low-alloy steel Plastic deformation Accumulated strain Cleavage cracks Cleavage fracture Cleavage mechanism Finite element method simulation Fracture surfaces Precracked specimens Relative location
收录类别	EI
语种	英语
EI入藏号	20124815728158
EI主题词	Fatigue of materials
来源库	Compendex
分类代码	951 Materials Science
文献类型	会议论文
条目标识符	https://ir.lut.edu.cn/handle/2XXMBERH/117153
专题	材料科学与工程学院_特聘教授组
作者单位	College of Materials Science and Engineering, State Key Laboratory for New Materials of Non-Ferrous Metal, Lanzhou University of Technology, Lanzhou, 730050, China
第一作者单位	兰州理工大学
推荐引用方式 GB/T 7714	Chen, J.H.,Wang, G.Z.. Mechanism of cleavage fracture of HSLA steel[C]:International Congress on Fracture,2005:3968-3973.