Life prediction based on analysis of crack coalescence in low cycle fatigue

Abstract The crack coalescence in some materials is known to make influence on the failure life significantly in low cycle fatigue as well as corrosion fatigue. A model was proposed to simulate crack linking during fatigue process. The crack distribution observed experimentally was idealized by a two-dimensional model with straight cracks. Some assumptions were made for the coalescence criterion in the model. A procedure for estimating residual life was developed based on the proposed model. The procedure was applied to fatigue process of a copper, in which the growth due to crack linkings was observed to be dominant through fatigue life. A good agreement was shown between the experimental and the predicted results. The statistical properties of life distribution were also discussed based on a Monte Carlo simulation.