Abstract
Database for the strength of materials is desired strongly as it is a powerful tool for searching out strength data. But as for fatigue properties, it is rarely possible to get suitable data to design or maintain machines and structures for a particular material and testing conditions directly from the database. In general, its fatigue properties must be estimated from the data obtained under similar testing conditions. In this paper, a method for predicting the missing properties in fatigue database is discussed.
Good correlations between the tensile property data and the exponents or coefficients of the equations for cyclic stress-strain curves and Manson-Coffin law were obtained for steels specified by JIS for machine structural use. By using these relationships, S-N curves under uniaxial tension-compression can be predicted for steels, if their tensile properties are known. A conversion method of fatigue strength is also proposed between rotating bending and uniaxial conditions or between reversed torsion and uniaxial conditions.
