Journal of Mechanical Science and Technology

  • 제20권5호
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  • Pages.621-633
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  • 2006
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  • 1738-494X(pISSN)
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  • 1976-3824(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
권호 표지

Deformation Analysis of Micro-Sized Material Using Strain Gradient Plasticity

  • Byon S.M. (Rolling Technology and Process Control Research Group, POSCO Technical Research Laboratories) ;
  • Lee Young-Seog (Department of Mechanical Engineering, Chung-Ang University)
  • 발행 : 2006.05.01
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초록

To reflect the size effect of material $(1\sim15{\mu}m)$ during plastic deformation of polycrystalline copper, a constitutive equation which includes the strain gradient plasticity theory and intrinsic material length model is coupled with the finite element analysis and applied to plane strain deformation problem. The method of least square has been used to calculate the strain gradient at each element during deformation and the effect of distributed force on the strain gradient is investigated as well. It shows when material size is less than the intrinsic material length $(1.54{\mu}m)$, its deformation behavior is quite different compared with that computed from the conventional plasticity. The generation of strain gradient is greatly suppressed, but it appears again as the material size increases. Results also reveal that the strain gradient leads to deformation hardening. The distributed force plays a role to amplify the strain gradient distribution.

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참고문헌

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