# 짧은균열의 피로성장거동

• 최용식 (성균관대학교 기계공학과) ;
• 홍성호 (한국가스공사 연구개발원) ;
• 우흥식 (동국대학교 산업안전공학과) ;
• 한지원 (호서대학교 산업안전공학과)
• Published : 1993.03.01

#### Abstract

The fatigue growth behavior of short cracks were studied various load ratios. Computer-aided unloading elastic compliance method was employed to measure the closure and the length of short cracks. In the dc/dN-$\Delta$K relationships. the decreasing behavior of the growth rate of short cracks is due to the decrease of crack opening ratio with increasing crack length. Irrespective of load ratio. the growth rate of short cracks can be well decribed in terms of the effective stress intensity factor range $\Delta$K$_{eff}$, which is calculated on the base of crack closure. dc/dN-$\Delta$K$_{eff}$ relationships of short cracks are found to coincide well with the corresponding long crack relationships. accordingly. the growth rate of short cracks can be predicted using that of long cracks.ort cracks can be predicted using that of long cracks.cks.