Crystallographic characterization of a phosphorus added TRIP steel

Texture and crystallographic orientation relationships, active during the transformation of austenite to bainite, are studied for two TRIP steels by means of Electron BackScatter Diffraction (EBSD). The texture measurements showed that the maximum intensity for the retained austenite was on the Brass component with the intensity gradually decreasing along the alpha and the beta fibre. The intensity of both BCC microconstituents was comparable and the bainite texture displayed clear transformation products that could be related with the dominant Brass component of the intercritical austenite. The study of the crystallographic orientation relationships showed that the Kurdjumov Sachs relationship was dominant. It was, however, also demonstrated that some precautions are necessary since a clear distinction between the evaluation of a small region of the microstructure and conclusions made for the complete material is required