Effect of crystallographic texture on the anisotropy of Charpy impact behavior in pipeline steel

The current study systematically investigated the anisotropy of fracture behavior in commercial API X100 pipeline steel. The experimental results showed that the temperature for transition from ductile to brittle fracture was significantly different in samples with different orientations, defined as anisotropy of fracture behavior in this paper. The inhomogeneity distribution of microstructure (grain size) and the crystallographic texture were systematically analyzed. The difference in grain size of the samples with different orientations can be reasonably ignored in this study. Therefore, the anisotropy of fracture behavior is attributed to the crystallographic textures in which the deformation and transformation texture components were included. The effect of crystallographic texture on the anisotropy of ductile to brittle fracture transition temperature was theoretically interpreted based on the relationship among yield strength, fracture strength, and their average orientation factor.