Fatigue Life Prediction by Elastic-Plastic Fracture mechanics for Surface Flaw Steel

J. Ocean Eng. Technol. 1995;9(2):112-122.

Gang Yong-Gu,Seo Chang-Min,Lee Jong-Sik

표면결함재에 관한 탄소성 파괴역학에 의한 피로수명 예측

강용구,서창민,이종식

금오공과대학교 기계설계공학과,경북대학교 공과대학 기계설계공학과,대우기술연구소 차체 설계실

Keywords: Crack Growth Equation, J-Integral Range, Cyclic stress-strain Curve, Life Prediction, Crack Growth Curve

핵심용어: 균열성장식, J-적분범위, 반복응력-변형률곡선, 수명예측, 균열성장곡선

Abstract

In this work, prediction of fatigue life and fatigue crack growth are studied. 4th order polynominal function is presented to describe the crack growth behaviors from artifical pit of SM45C steel. Crack growth curves obtained from 4th order polyminal growth equations are in good agreement with experimental data The crack growth behaviors at arbitrary stress levels and investigated by the concept of elastic-plastic fracture mechanics using ${Delta}J$. Fatigue life prediction are carried out by numerical integral method. Prediction lives obtained by proposed method in this study, is in good agreement with the experimental ones. Life prediction results calculated by using of ${Delta}J$ better than those of ${Delta}K$.