A large-scale database MSDRD on mechanical properties of structural materials such as metals, composites and ceramics was constructed by The Research Group for Statistical Aspects of Materials Strength. In this study, fatigue data of carbon steels and alloy steels for machine structural use are obtained from the present database and distribution characteristics of fatigue properties are analyzed by a statistical procedure developed by the authors. It is found that fatigue lives of the respective steels have a complicated distribution pattern depending on the stress level and that mixed-mode Weibull distribution is preferable to represent the fatigue life distribution in a wide variety of steels and a wide range of stress levels. In fact, statistical fatigue properties thus analyzed are in good agreement with the experimental data filed in MSDRD and analytical results are applicable to the reliability design of mechanical structures.
