Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Finite Element Simulation of Fracture Toughness Test

파괴인성시험의 유한요소 시뮬레이션

  • Chu, Seok Jae (School of Mechanical Engineering, Univ. of Ulsan) ;
  • Liu, Conghao (School of Mechanical Engineering, Univ. of Ulsan)
  • 주석재 (울산대학교 기계공학부) ;
  • 류총호 (울산대학교 기계공학부)
  • Received : 2012.08.30
  • Accepted : 2012.12.04
  • Published : 2013.04.01
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Abstract

Finite element simulations of tensile tests were performed to determine the equivalent stress - equivalent plastic strain curves, critical equivalent stresses, and critical equivalent plastic strains. Then, the curves were used as inputs to finite element simulations of fracture toughness tests to determine the plane strain fracture toughness. The critical COD was taken as the COD when the equivalent plastic strain at the crack tip reached a critical value, and it was used as a crack growth criterion. The relationship between the critical COD and the critical equivalent plastic strain or the reduction of area was found. The relationship between the plane strain fracture toughness and the product of the critical equivalent stress and the critical equivalent plastic strain was also found.

인장시험을 유한요소 시뮬레이션하여 등가응력-등가소성변형률 곡선, 임계 등가응력과 임계 등가소성변형률을 결정하였다. 그리고, 이 곡선을 입력하여 파괴시험을 유한요소 시뮬레이션하여 평면변형률 파괴인성치를 결정하여 보려고 하였다. 균열선단절점에서 등가소성변형률이 임계 등가소성변형률에 도달할 때 균열개구변위를 임계 균열개구변위로 취하여 균열성장조건으로 사용되었다. 임계 등가소성변형률이나 단면감소율과 파괴시험 임계 균열개구변위와 관련성을 찾아보고, 임계 등가응력과 임계 등가소성변형률을 동시에 적용하여 파괴시험 파괴인성치와의 관련성도 찾아보았다.

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References

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