A Local Approach for Fatigue Life Analysis of Notched Components

Abstract From the author's previous study, it is sure that the local approach for fracture analysis of notched components under static loading proposed by the author established on the basis of linear elastic mechanics is suitable for both brittle materials and ductile materials. The applicability relies on the fact that the mechanical intensity parameter used in the local approach is the stress-based intensity parameter. In this study, an attempt is made that the local approach for fracture analysis of sharp notches under static loading proposed by the author is extended to fatigue loading. Under the assumption that the empirical equation of determining the fracture toughness under static loading proposed by the author is properly employed under fatigue loading, a local approach+ for the fatigue life analysis of notched components is proposed in this study. It is a united method that combines the local approach proposed by the author with the empirical equation of determining the fracture toughness proposed by the author for fatigue life analysis of notched components. According to the local approach+, the basic fatigue test data required to be known are a set fatigue life test data of the plain material studied and a set fatigue life test data of a notched material (sample notch). By using the two sets of fatigue life test data, S–N equation of any notch can be predicted by the local approach+. Validation verification by experimental data from the literature shows that, by the predicted S–N equation, the fatigue life analysis results are very satisfactory.