Competing deformation mechanisms in nanocrystalline metals and alloys: Coupled motion versus grain boundary sliding

被引:73
作者
Schaefer, Jonathan [1 ]
Albe, Karsten [1 ]
机构
[1] Tech Univ Darmstadt, Fachbereich Mat & Wissensch, Fachgebiet Mat Modellierung, D-64287 Darmstadt, Germany
关键词
Nanocrystalline materials; Grain boundary segregation; Plastic deformation; Molecular dynamics; MOLECULAR-DYNAMICS SIMULATION; CU; COPPER; MICROSTRUCTURE; INTERFACES; MIGRATION; ROTATION; STRESS;
D O I
10.1016/j.actamat.2012.07.044
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Plastic deformation of nanocrystalline Pd and Cu as well as the demixing systems Cu-Nb and Cu-Fe is studied by means of atomic-scale computer simulations. The microstructures are specifically chosen to facilitate mesoscopic grain boundary sliding. The influence of segregating solutes on the deformation mechanisms is studied and different cases of solute distributions are compared. We find that the competition between mesoscopic grain boundary sliding and coupled grain boundary motion is controlled by the concentration and distribution of segregating solutes. By analyzing the microstructural evolution and dislocation activity we make a connection between the atomistic solute distribution and the mechanisms of deformation, explaining the observed stress-strain behavior. The detailed analysis of the normal grain boundary motion reveals a stick-slip behavior and a coupling factor which is consistent with results from bicrystal simulations. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:6076 / 6085
页数:10
相关论文
共 42 条
[1]   MOLECULAR-DYNAMICS WITH COUPLING TO AN EXTERNAL BATH [J].
BERENDSEN, HJC ;
POSTMA, JPM ;
VANGUNSTEREN, WF ;
DINOLA, A ;
HAAK, JR .
JOURNAL OF CHEMICAL PHYSICS, 1984, 81 (08) :3684-3690
[2]   Grain coarsening during compression of bulk nanocrystalline nickel and copper [J].
Brandstetter, S. ;
Zhang, Kai ;
Escuadro, A. ;
Weertman, J. R. ;
Van Swygenhoven, H. .
SCRIPTA MATERIALIA, 2008, 58 (01) :61-64
[3]   Coupling grain boundary motion to shear deformation [J].
Cahn, John W. ;
Mishin, Yuri ;
Suzuki, Akira .
ACTA MATERIALIA, 2006, 54 (19) :4953-4975
[4]   A unified approach to motion of grain boundaries, relative tangential translation along grain boundaries, and grain rotation [J].
Cahn, JW ;
Taylor, JE .
ACTA MATERIALIA, 2004, 52 (16) :4887-4898
[5]   Structure of Kurdjumov-Sachs interfaces in simulations of a copper-niobium bilayer [J].
Demkowicz, M. J. ;
Hoagland, R. G. .
JOURNAL OF NUCLEAR MATERIALS, 2008, 372 (01) :45-52
[6]   Variable-charge method applied to study coupled grain boundary migration in the presence of oxygen [J].
Elsener, A. ;
Politano, O. ;
Derlet, P. M. ;
Van Swygenhoven, H. .
ACTA MATERIALIA, 2009, 57 (06) :1988-2001
[7]   Short-range order and precipitation in Fe-rich Fe-Cr alloys: Atomistic off-lattice Monte Carlo simulations [J].
Erhart, Paul ;
Caro, Alfredo ;
de Caro, Magdalena Serrano ;
Sadigh, Babak .
PHYSICAL REVIEW B, 2008, 77 (13)
[8]   Revealing Extraordinary Intrinsic Tensile Plasticity in Gradient Nano-Grained Copper [J].
Fang, T. H. ;
Li, W. L. ;
Tao, N. R. ;
Lu, K. .
SCIENCE, 2011, 331 (6024) :1587-1590
[9]  
Foiles S.M., 2001, TECHNICAL REPORT
[10]   Grain-size stabilization by impurities and effect on stress-coupled grain growth in nanocrystalline Al thin films [J].
Gianola, D. S. ;
Mendis, B. G. ;
Cheng, X. M. ;
Hemker, K. J. .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2008, 483-84 (1-2 C) :637-640