Relations between the S-N, ε-N and da/dN-ΔK curves of materials

Abstract

The S-N, ε-N and da/dN-ΔK curves are the basic data of fatigue property for materials, and they are used in the stress-life method, the local strain method and the LEFM (Linear elastic fracture mechanics) crack propagation method to predict fatigue life of structures, respectively. In the present paper, the relations between these fatigue curves and their probability of predicting each other were discussed through several fatigue-life models. The discussed subjects include (1) predicting the S-N curves from the da/dN-ΔK curves of materials, (2) predicting the S-N curves from the ε-N curves, and (3) predicting the da/dN-ΔK curves from the ε-N curves. It is shown that there are certain relations between the S-N, -N and da/dN-ΔK curves of materials and it is predictable from one curve to another. © Shen et al.; Licensee Bentham Open.