The Correlation between Fatigue Fracture Crack Surface Friction and Crack Closure Effect in Crack Growth under Mixed-mode loading

혼합모드 하중 하에서의 균열성장 중 피로파단면 마찰과 균열닫힘효과의 상호관계

  • 서기정 (고려대학교 대학원 기계공학과) ;
  • 송삼홍 (고려대학교 기계공학과) ;
  • 이정무 (고려대학교 공학기술연구소)
  • Published : 2004.11.03

Abstract

Crack tip behavior of single mode loading condition(mode I)depend on tensile loading component but one of mixed mode loading condition(mode I+II) have influenced on shear loading component like the practical structure. Because crack closure is caused by shear loading component under mixed-mode loading a research on the behavior in the stage of crack initiation and propagation require to be evaluate about crack closure effect by fatigue crack surface friction. For that reasion we examined the behavior at the crack tip by direct measuring method. Measured behavior at the crack tip was analyzed through vector crack tip displacement. As a result, crack propafation equation was corrected by considering with crack closure effect. In addition we compared fatigue fracture crack surface and crack closure level.