Influence of Density Variation on Stress and Displacement Fields at a Propagating Mode-III Crack Tip in Orthotropic Functionally Graded Materials

밀도변화가 직교이방성함수구배재료에서 전파하는 모드 III 균열선단의 응력 및 변위장에 미치는 영향

  • Lee, Kwang-Ho (Dept. of Automotive Engineering, Kyungpook Nat'l Univ.)
  • 이광호 (경북대학교 자동차공학부)
  • Received : 2011.05.16
  • Accepted : 2011.07.26
  • Published : 2011.09.01


The influences of density variation on stress and displacement fields at a propagating Mode-III crack tip in orthotropic functionally graded materials (OFGMs) are studied. The crack propagates dynamically at a right angle to the gradient of physical properties. Three kinds of elasticity and density gradients are analyzed in this study. They are as follows: (1) the density varies without elasticity variation, (2) the directions of the density and elasticity gradients are opposite to each other, and (3) same. For these cases, the stress and displacement fields at the crack tip are developed and the dynamic stress intensity factors for propagating cracks are also studied. When the crack speed is low, the influence of density variation on the stresses and displacement is low. However, when the crack speed is high, this influence is very high.


Variation of Density and Elasticity;Dynamic Stress Intensity Factors;Orthotropic Functionally Graded Materials;Propagating Crack;Stress and Displacement Fields


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