Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening

doi:10.1016/j.jmps.2024.105869

IMECH-IR > 非线性力学国家重点实验室

	Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening
	Meng, Jia 1; Peng, Shenyou1 ; Fang, Qihong 1; Li, Jia 1; Wei YJ(魏宇杰)2,3
通讯作者	Peng, Shenyou([email protected]) ; Wei, Yujie([email protected])
发表期刊	JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
	2024-12-01
卷号	193 页码:16
ISSN	0022-5096
摘要	In the endeavors of working with microstructures in polycrystalline metals for better strength and ductility, grain boundaries (GBs) are placed at the front burner for their pivotal roles in plastic deformation. Often the mechanical properties of polycrystalline metals are governed by mutual interactions among GBs and dislocations. A thorough comprehension of GB deformation is therefore critical for the design of metals of superb performance. In this research, we investigated the mechanical behavior of symmetric tilt grain boundaries in face-centered cubic (F.C.C.) nickel, which may be subject to tension, shearing, and mixing-mode load using molecular dynamics simulations. We observed that (1) there exist four types of micro deformation mechanisms in GBs, and illustrate at the atomistic scale their distinctions and their dependence on the activation of lattice slip in the crystal; (2) GBs are intrinsically brittle under tension but exhibit ductile behavior during shearing. Shifting from pure tension with increasing shear component during mixing-mode load leads to GB toughening; and (3) there lacks conceivable dependence of GB tensile strength on tilted GBs, in contrast to a relatively rough trend of greater shear strength in GBs of large misorientation. GB energy shows no direct connection with GB strength, as broadly reported in existing literature. This research enhances our mechanistic understanding of GB plasticity in crystalline metals, and points to a potential way of making strong-yet-tough polycrystalline metals through GB engineering: in addition to GB structure manipulation, tuning the loading mode of GBs may open another avenue for their better performance.
关键词	Grain boundary Misorientation Tensile brittleness Shear toughening Brittle-ductile transition
DOI	10.1016/j.jmps.2024.105869
收录类别	SCI ; EI
语种	英语
WOS记录号	WOS:001320625500001
关键词[WOS]	NANOCRYSTALLINE METALS ; ATOMISTIC SIMULATION ; SYMMETRIC TILT ; MIGRATION ; STRESS ; DIFFUSION ; MODEL ; DEFORMATION ; NUCLEATION ; MECHANISM
WOS研究方向	Materials Science ; Mechanics ; Physics
WOS类目	Materials Science, Multidisciplinary ; Mechanics ; Physics, Condensed Matter
资助项目	NSFC (National Natural Science Foundation of China) Basic Science Center for 'Multiscale Problems in Nonlinear Mechanics'[11988102] ; NSFC[12102133]
项目资助者	NSFC (National Natural Science Foundation of China) Basic Science Center for 'Multiscale Problems in Nonlinear Mechanics' ; NSFC
论文分区	一类/力学重要期刊
力学所作者排名	1
RpAuthor	Peng, Shenyou ; Wei, Yujie
引用统计
文献类型	期刊论文
条目标识符	http://dspace.imech.ac.cn/handle/311007/96884
专题	非线性力学国家重点实验室
作者单位	1.Hunan Univ, Coll Mech & Vehicle Engn, Changsha 410082, Peoples R China; 2.Chinese Acad Sci, Inst Mech, LNM, Beijing 100190, Peoples R China; 3.Univ Chinese Acad Sci, Sch Engn Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Meng, Jia,Peng, Shenyou,Fang, Qihong,et al. Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening[J]. JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS,2024,193:16.Rp_Au:Peng, Shenyou, Wei, Yujie
APA	Meng, Jia,Peng, Shenyou,Fang, Qihong,Li, Jia,&魏宇杰.(2024).Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening.JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS,193,16.
MLA	Meng, Jia,et al."Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening".JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 193(2024):16.