On the Anisotropy of Low-Cycle Fatigue Properties of Rolled Plates

Abstract

In order to gather information relating to the low-cycle fatigue behavior of anisotropic materials, the low-cycle fatigue prorerties of thick rolled steel plates were investigated in several directions under the condition of uniaxial tension-compression. The steel plates used showed considerable anisotropy in fracture ductility in the thickness direction, while anisotropy in the yield and ultimate tensile strengths was observed to be very slight in any direction. The low-cycle fatigue behavior was also the most anisotropic in the thickness direction. The fracture life in a given direction, however, was found to follow the Manson-Coffin type relation, which is usually applied to isotropic materials, if the fracture ductility determined from the tensile test in that direction was used. The crack initiation life also exhibited a similar trend, although in a more exaggerated manner. Differences were found in fracture mode depending on the directions relative to the rolling direction.