Molecular dynamics studies of thermal dissipation during shock induced   spalling

doi:10.1063/1.4821341

CORC > 北京大学 > 工学院

	Molecular dynamics studies of thermal dissipation during shock induced spalling
	Xiang, Meizhen ; Hu, Haibo ; Chen, Jun ; Liao, Yi
刊名	应用物理杂志
	2013
关键词	VOID GROWTH PLASTIC-DEFORMATION HIGH-TEMPERATURES DUCTILE FRACTURE METALS SOLIDS SPALLATION SIMULATION NUCLEATION
DOI	10.1063/1.4821341
英文摘要	Under shock loadings, the temperature of materials may vary dramatically during deformation and fracture processes. Thus, thermal effect is important for constructing dynamical failure models. Existing works on thermal dissipation effects are mostly from meso-to macro-scale levels based on phenomenological assumptions. The main purpose of the present work is to provide several atomistic scale perspectives about thermal dissipation during spall fracture by nonequilibrium molecular dynamics simulations on single-crystalline and nanocrystalline Pb. The simulations show that temperature arising starts from the vicinity of voids during spalling. The thermal dissipation rate in void nucleation stage is much higher than that in the later growth and coalescence stages. Both classical spallation and micro-spallation are taken into account. Classical spallation is corresponding to spallation phenomenon where materials keep in solid state during shock compression and release stages, while micro-spallation is corresponding to spallation phenomenon where melting occurs during shock compression and release stages. In classical spallation, whether residuary dislocations are produced in pre-spall stages has significant influences on thermal dissipation rate during void growth and coalescence. The thermal dissipation rates decrease as shock intensity increases. When the shock intensity exceeds the threshold of micro-spallation, the thermal dissipation rate in void nucleation stage drops precipitously. It is found that grain boundaries mainly influence the thermal dissipation rate in void nucleation stage in classical spallation. In micro-spallation, the grain boundary effects are insignificant. (C) 2013 AIP Publishing LLC.; Physics, Applied; SCI(E); EI; 0; ARTICLE; 12; 114
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/220676]
专题	工学院
推荐引用方式 GB/T 7714	Xiang, Meizhen,Hu, Haibo,Chen, Jun,et al. Molecular dynamics studies of thermal dissipation during shock induced spalling[J]. 应用物理杂志,2013.
APA	Xiang, Meizhen,Hu, Haibo,Chen, Jun,&Liao, Yi.(2013).Molecular dynamics studies of thermal dissipation during shock induced spalling.应用物理杂志.
MLA	Xiang, Meizhen,et al."Molecular dynamics studies of thermal dissipation during shock induced spalling".应用物理杂志 (2013).