Effect of dislocation density-twin interactions on twin growth in AZ31 as revealed by explicit crystal plasticity finite element modeling

被引:113
作者
Ardeljan, Milan [1 ]
Beyerlein, Irene J. [2 ]
Knezevic, Marko [1 ]
机构
[1] Univ New Hampshire, Dept Mech Engn, 33 Acad Way,Kingsbury Hall,W119, Durham, NH 03824 USA
[2] Univ Calif Santa Barbara, Dept Mat, Dept Mech Engn, Santa Barbara, CA 93106 USA
基金
美国国家科学基金会;
关键词
Twinning; Microstructures; Crystal plasticity; Finite elements; Dislocation density; STRAIN-PATH CHANGES; X-RAY-DIFFRACTION; DEFORMATION-BEHAVIOR; TEXTURE EVOLUTION; GRAIN-BOUNDARIES; POLYCRYSTAL PLASTICITY; MECHANICAL RESPONSE; TENSION-COMPRESSION; ZONAL DISLOCATIONS; PROPERTY CLOSURES;
D O I
10.1016/j.ijplas.2017.09.002
中图分类号
TH [机械、仪表工业];
学科分类号
0802 ;
摘要
In this work, we employ the recently developed framework for the explicit modeling of discrete twin lamellae within a three-dimensional (3D) crystal plasticity finite element (CPFE) model to examine the effects of dislocation densities in the twin domain on twin thickening. Simulations are carried out for {(1) over bar 012}< 10 (1) over bar1 > extension twins in a magnesium AZ31 alloy. The model for the twin lamellae accounts for the crystallographic twin matrix orientation relationship and characteristic twin shear transformation strain. The calculations for the mechanical fields as a result of twinning consider that one of three types of twin-dislocation density interactions have occurred. One case assumes that the expanding twin retains in its domain the same dislocation density as the parent. The second one considers that twin expansion has lowered the dislocation density as the twin thickens, and the last one, the Basinski effect, assumes that when twin sweeps the region, the dislocation density incorporated in the twin domain is amplified. In the modeling approach, the twin is thickened according to a criterion that maintains the stress state in the vicinity of the grain at a pre-defined characteristic twin resistance. The calculations show that most of the averaged properties, such as the rate of dislocation storage in the entire twin grain, the twin growth rate, the stress field in the twinned grain and neigh-boring grains, and the slip activity in the parent matrix are not significantly altered by dislocation storage in the twin. The results indicate that, however, the slip activity in the twinned domain is affected. In particular, in the increased dislocation density case, the rate of dislocation density in the twin domain increases at low strains when the twin is first growing from 2% to 5% volume fraction. This initial boost in the dislocation density storage rate causes the newly expanded dislocation twin to contain more stored dislocations than the other cases for all strain levels. Another interesting difference concerns the preference for one or two twins for the same total twin volume fraction; for the increased dislocation twin or twin that retains the dislocation density as it grows, formation of two twins is favored. For a twin that removes dislocation density, only one twin is preferred. The results imply that in the case with reduced dislocation density leads to lower stored dislocations and dislocation storage rates, and lower pyramidal slip activity. (C) 2017 Elsevier Ltd. All rights reserved.
引用
收藏
页码:81 / 101
页数:21
相关论文
共 78 条
[1]   Strain rate and temperature sensitive multi-level crystal plasticity model for large plastic deformation behavior: Application to AZ31 magnesium alloy [J].
Ardeljan, Milan ;
Beyerlein, Irene J. ;
McWilliams, Brandon A. ;
Knezevic, Marko .
INTERNATIONAL JOURNAL OF PLASTICITY, 2016, 83 :90-109
[2]   A study of microstructure-driven strain localizations in two-phase polycrystalline HCP/BCC composites using a multi-scale model [J].
Ardeljan, Milan ;
Knezevic, Marko ;
Nizolek, Thomas ;
Beyerlein, Irene J. ;
Mara, Nathan A. ;
Pollock, Tresa M. .
INTERNATIONAL JOURNAL OF PLASTICITY, 2015, 74 :35-57
[3]   Explicit incorporation of deformation twins into crystal plasticity finite element models [J].
Ardeljan, Milan ;
McCabe, Rodney J. ;
Beyerlein, Irene J. ;
Knezevic, Marko .
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, 2015, 295 :396-413
[4]   A dislocation density based crystal plasticity finite element model: Application to a two-phase polycrystalline HCP/BCC composites [J].
Ardeljan, Milan ;
Beyerlein, Irene J. ;
Knezevic, Marko .
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS, 2014, 66 :16-31
[5]   OVERVIEW .42. TEXTURE DEVELOPMENT AND STRAIN-HARDENING IN RATE DEPENDENT POLYCRYSTALS [J].
ASARO, RJ ;
NEEDLEMAN, A .
ACTA METALLURGICA, 1985, 33 (06) :923-953
[6]   Evolution of stress in individual grains and twins in a magnesium alloy aggregate [J].
Aydiner, C. C. ;
Bernier, J. V. ;
Clausen, B. ;
Lienert, U. ;
Tome, C. N. ;
Brown, D. W. .
PHYSICAL REVIEW B, 2009, 80 (02)
[7]   COPPER SINGLE-CRYSTAL PSB MORPHOLOGY BETWEEN 4.2-K AND 350-K [J].
BASINSKI, ZS ;
BASINSKI, SJ .
ACTA METALLURGICA, 1989, 37 (12) :3263-3273
[8]   The transformation of slip dislocations during twinning of copper-aluminum alloy crystals [J].
Basinski, ZS ;
Szczerba, MS ;
Niewczas, M ;
Embury, JD ;
Basinski, SJ .
REVUE DE METALLURGIE-CAHIERS D INFORMATIONS TECHNIQUES, 1997, 94 (09) :1037-1043
[9]  
Bathe KJ., 1996, Finite element procedures
[10]   THE DYNAMICS OF TWINNING AND THE INTERRELATION OF SLIP AND TWINNING IN ZINC CRYSTALS [J].
BELL, RL ;
CAHN, RW .
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1957, 239 (1219) :494-&