Method for estimating failure probabilities of structural components and its application to fatigue problem of internally cooled superconductor

A method of assessing the fatigue life of a component containing defects is presented. The method incorporates a probabilistic approach into the CEGB two-criteria method. The aspect ratio of the initial defect, the proportional coefficient of the fatigue crack growth law, and the threshold stress intensity range are assumed to be treated as random variables in the method. Examples are given to illustrate the method´s application to the reliability analysis of the conduit for an internally cooled cabled superconductor (ICCS) subjected to cyclic quench pressure. The possible failure mode and mechanical properties contributing to the fatigue life of the thin conduit are discussed using analytical and experimental results