Development of an Approximate Model for Ultrasonic Evaluation of Small Surface Fatigue Cracks

작은 피로 균열의 초음파 평가를 위한 근사 모델의 개발

  • Kang, Kae-Myung (Department of Materials Engineering, Seoul National University of Technology) ;
  • Kim, Jin-Yeon (The Ohio State University, Department of Welding Engineering)
  • Received : 2000.01.15
  • Accepted : 2000.05.22
  • Published : 2000.06.30

Abstract

A theoretical model for the evaluation of small surface fatigue crack initiated from a pit-type surface flaw is presented. The low frequency scattering model is developed based on the reciprocity principle for the elastic wave scattering. The effect of the flaw on the surface wave reflection from the crack is taken into account approximately by means of the stress intensity factor of cracks on a through thickness hole. The reflection coefficient of surface wave is derived for the prediction of small surface crack depth. Calculated results for pits with different sizes are illustrated.

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