Effect of Extrinsic Grain Boundary Dislocations on Mechanical Properties of Ultrafine-Grained Metals by Molecular Dynamics Simulations

被引：13

作者：

Shimokawa, Tomotsugu ^{[1
]}

Hiramoto, Tomoyuki ^{[2
]}

Kinari, Toshiyasu ^{[1
]}

Shintaku, Sukenori ^{[1
]}

机构：

[1] Kanazawa Univ, Grad Sch Nat Sci & Technol, Div Innovat Technol & Sci, Kanazawa, Ishikawa 9201192, Japan

[2] Kanazawa Univ, Grad Sch Nat Sci & Technol, Div Mech Sci & Engn, Kanazawa, Ishikawa 9201192, Japan

来源：

MATERIALS TRANSACTIONS | 2009年 / 50卷 / 01期

关键词：

extrinsic grain boundary dislocation; grain boundary sliding; grain boundary migration; nonequilibrium grain boundary; shielding effect; grain boundary structure; molecular dynamics; SEVERE PLASTIC-DEFORMATION; STRAIN-RATE; ARB; NANOCRYSTALLINE; DUCTILITY; CU;

D O I：

10.2320/matertrans.MD200810

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The effect of extrinsic grain boundary dislocations (EGBDs) in nonequilibrium grain boundaries on the mechanical properties of ultrafinegrained metals is investigated by molecular dynamics simulations. Aluminum bicrystal models containing cracks and EGBDs impinged from the crack tips are prepared. First, the dependence of the local grain boundary structure on the accommodation mechanism of EGBDs. and on its stress field is Studied. Then, the shielding effect of EGBDs on the emissions of dislocations from crack tips is investigated, and the effect of nonequilibrium grain boundaries on the intragranular deformation is discussed. Finally, to investigate the relationship between EGBDs and intergranular deformations, shear loading is applied to the bicrystal models. It is found that extrinsic grain boundaries function as the intergranular deformation source, and the Burgers vector components of the EGBDs lead to anisotropic grain boundary sliding. [doi: 10.2320/matertrans.MD200810]

引用

页码：2 / 10

页数：9

共 28 条

[1]

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