# 입자 강화 금속기지 복합재의 연속체 강도해석을 위한 전위 펀칭 이론의 전산적 평가

• 서영성 (한남대학교 기계공학과) ;
• 김용배 (한남대학교 기계공학과)
• Accepted : 2011.01.04
• Published : 2011.03.01
• 65 30

#### Abstract

The yield strength of particle-reinforced composites increases as the size of the particle decreases. This kind of length scale has been mainly attributed to the geometrically necessary dislocation punched around the particle as a result of the mismatch of the thermal expansion coefficients of the particle and the matrix when the composites are cooled down after consolidation. In this study, two dislocation-punching theories that can be used in continuum structural modeling are assessed numerically. The two theories, presented by Shibata et al. and Dunand and Mortensen, calculate the size of the dislocationpunched zone. The composite yield strengths predicted by finite element analysis were qualitatively compared with experimental results. When the size of the particle is less than $2{\mu}m$, the patterns of the composite strength are quite different. The results obtained by Shibata et al. are in qualitatively better agreement with the experimental results.

#### Keywords

Particle-Reinforced Metal Matrix Composites;Dislocation Punching;Geometrically Necessary Dislocation;Length Scale;Finite-Element Analysis;Numerical Assessment

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