Study on anisotropy in microstructure and tensile properties of the 12Cr oxide dispersion strengthened (ODS) steel

Microstructure and tensile properties ranged from ambient temperature to 700 ℃ of the 12Cr ODS steel were investigated by scanning electron microscopy, electron backscatter diffraction technique, and tensile tests. Results show that microstructure is composed of elongated grains with axis parallel to rolling direction. Ultimate tensile strength and 0.2% offset yield strength gradually decrease with increasing test temperature. Uniform elongation and total elongation reduce with the temperature rising up to 500 ℃, whereas increase at higher temperatures due to activation of slip systems. Moreover, ductility in rolling direction is better than that in transverse direction. Fracture surfaces suggest that a large number of small and uniform dimples, and predominant cleavage-like facets present in rolling direction, and transverse direction, respectively.