Twin boundary spacing effects on shock response and spall behaviors of hierarchically nanotwinned fcc metals

IMECH-IR > 非线性力学国家重点实验室

	Twin boundary spacing effects on shock response and spall behaviors of hierarchically nanotwinned fcc metals
	Yuan FP(袁福平); Chen L; Jiang P(姜萍); Wu XL(武晓雷); Yuan, FP (reprint author), Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, 15 North 4th Ring,West Rd, Beijing 100190, Peoples R China.
发表期刊	Journal of Applied Physics
	2014-02-14
卷号	115 期号:6 页码:63509
ISSN	0021-8979
摘要	Atomistic deformation mechanisms of hierarchically nano-twinned (NT) Ag under shock conditions have been investigated using a series of large-scale molecular dynamics simulations. For the same grain size d and the same spacing of primary twins lambda(1), the average flow stress behind the shock front in hierarchically NT Ag first increases with decreasing spacing of secondary twins lambda(2), achieving a maximum at a critical lambda(2), and then drops as lambda(2) decreases further. Above the critical lambda(2), the deformation mechanisms are dominated by three type strengthening mechanisms: (a) partial dislocations emitted from grain boundaries (GBs) travel across other boundaries; (b) partial dislocations emitted from twin boundaries (TBs) travel across other TBs; (c) formation of tertiary twins. Below the critical lambda(2), the deformation mechanism are dominated by two softening mechanisms: (a) detwinning of secondary twins; (b) formation of new grains by cross slip of partial dislocations. Moreover, the twin-free nanocrystalline (NC) Ag is found to have lower average flow stress behind the shock front than those of all hierarchically NT Ag samples except the one with the smallest lambda(2) of 0.71 nm. No apparent correlation between the spall strength and lambda(2) is observed in hierarchically NT Ag, since voids always nucleate at both GBs and boundaries of the primary twins. However, twin-free NC Ag is found to have higher spall strength than hierarchically NT Ag. Voids can only nucleate from GBs for twin-free NC Ag, therefore, twin-free NC Ag has less nucleation sources along the shock direction when compared to hierarchically NT Ag, which requiring higher tensile stress to create spallation. These findings should contribute to the understandings of deformation mechanisms of hierarchically NT fcc metals under extreme deformation conditions. (C) 2014 AIP Publishing LLC.
学科领域	Physics
URL	查看原文
收录类别	SCI ; EI
语种	英语
WOS记录号	WOS:000331839800019
项目资助者	The authors would like to acknowledge the financial support of the National Key Basic Research Program of China (Grants Nos. 2012CB932203 and 2012CB937500) and NSFC (Grants Nos. 11002151, 11222224, 11072243, 51301187, and 11021262). The simulations reported were performed at Supercomputing Center of Chinese Academy of Sciences.
课题组名称	LNM材料介观力学性能的表征
论文分区	二类/Q2
引用统计	被引频次：23[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://dspace.imech.ac.cn/handle/311007/48790
专题	非线性力学国家重点实验室
通讯作者	Yuan, FP (reprint author), Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, 15 North 4th Ring,West Rd, Beijing 100190, Peoples R China.
推荐引用方式 GB/T 7714	Yuan FP,Chen L,Jiang P,et al. Twin boundary spacing effects on shock response and spall behaviors of hierarchically nanotwinned fcc metals[J]. Journal of Applied Physics,2014,115,6,:63509.
APA	Yuan FP,Chen L,Jiang P,Wu XL,&Yuan, FP .(2014).Twin boundary spacing effects on shock response and spall behaviors of hierarchically nanotwinned fcc metals.Journal of Applied Physics,115(6),63509.
MLA	Yuan FP,et al."Twin boundary spacing effects on shock response and spall behaviors of hierarchically nanotwinned fcc metals".Journal of Applied Physics 115.6(2014):63509.

条目包含的文件		下载所有文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
IMCAS-J2014-090.pdf（11355KB）			开放获取	--	浏览下载