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 <110> 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.