Method and system for probabilistic fatigue crack life estimation

The present invention relates to probabilistic estimation of fatigue crack life of a component configured for being subjected cyclic stress. A plurality of representations of the component are defined from material property scatter data (90a-g) and flaw-size scatter data (90h-j) of the component, wherein each representation is defined by one possible material condition and flaw-size condition associated with the component. For each individual representation, a component location is selected (93) and a determination (96) is made whether said individual representation fails after a given number of cycles N, based on the calculation (95) of a crack growth in the selected location. The crack growth is calculated (95) on the basis of the material condition and the flaw-size condition in the selected location. Failure of the individual representation is determined (96) if the crack growth is determined to be unstable. The sum total of the number of the representations that failed after N cycles is determined (97). A probability of failure of the component after N cycles is then determined (99) as PoF(N)=Nf/S, wherein PoF(N) is the probability of failure of the component after N cycles, Nf is the sum total of the number of representations that are determined to have failed after N cycles, and S is the total number of representations.