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Variation of A2 with Crack Propagation in a Ductile Metal; Experimental Evaluation

연성재료의 균열진전에 따른 A2의 변화; 실험적 측정

  • 김헌중 (전남대학교 대학원 기계공학과) ;
  • 김동학 (전남대학교 대학원 기계공학과) ;
  • 양경진 (전남대학교 대학원 기계공학과) ;
  • 강기주 (전남대학교 기계시스템공학부)
  • Published : 2003.01.01

Abstract

A way to measure the second parameter $A_2$of CT specimens is described. The displacement $\delta$$_{5}$ which is measured continuously from visual images of the lateral surface during crack growth is used to calculate the A, as a function of crack growth. The crack length is measured by DCPD(Direct Current Potential Drop) method and the J-resistance curve is determined according to ASTM standard E1737-96. To prove the validity of this method, three dimensional finite element analyses were performed, and variations of the displacements $\delta$$_{5}$ and $A_2$along the thickness were explored. As the result, it has been shown that the $\delta$$_{5}$ measured from the visual images of the lateral surface and the corresponding $A_2$can be regarded as the average through the thickness for 1T and 1/2T specimens of SA106Gr.C steel.steel.

Keywords

J-$A_2$Theory;J-R Curve;CT Specimen;Finite Element Method

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