Analysis of microbending tests for polycrystalline materials using the modified strain gradient theory

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:49

Article

Jung, Bong-bu¹  Lee, Hun-kee²  Park, Hyun-chul¹ 

[1] POSTECH, Dept Mech Engn, Pohang 790784, Gyungbuk, South Korea

[2] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA

关键词: Bending test;    GNDs;    Size effect;    Characteristic length;    Strain gradient plasticity;   

DOI  :  10.1016/j.ijsolstr.2012.04.011

来源: Elsevier

【 摘 要 】

A modified strain gradient theory is proposed based on the nonhomogeneity of polycrystalline metallic materials and free surface effects. Consideration of the geometrically necessary dislocations on the grain boundary and the free surface effect suggests a relationship between the characteristic length, specimen size and grain size. This relationship can explain the size effects and flow stress in micro/nanoscale structures. We will propose a new model for bending tests using the modified strain gradient plasticity theory. Using the proposed model, bending behavior of polycrystalline materials in micron-scale structures is investigated, and compared with experimental results from other researchers. (C) 2012 Elsevier Ltd. All rights reserved.

【 授权许可】

Free