FATIGUE CRACK INITIATION MODEL OF TYPE 316 STAINLESS STEEL

The fatigue tests under different conditions of strain range were conducted in air and the replica observation of fatigue cracks on specimen surface was also conducted. Using data obtained in fatigue tests, statistical dispersion of crack initiation life was quantified and modeled through an application of two parameter Weibull distribution. The relationship between strain range and two parameters (s, shape parameter and eta, scale parameter) of crack initiation model was discussed. Thereby, the applicability of crack initiation model for arbitrary strain range was shown. Furthermore, the validation of P-curve applied crack initiation model was conducted by the simulation of fatigue life.