LAUSR

Abstract One material with the same chemical composition as CLF-1 steel (defined as “base”) and three carbide dispersion strengthened CLF-1 steels with Al4C3, Ti3SiC2 and Cr2AlC additions were fabricated (defined as “+Al4C3”, “+Ti3SiC2”, and “+Cr2AlC” steel), respectively, via mechanical alloying and hot isostatic pressing (HIP). The room temperature ultimate tensile strength (UTS) of the as-HIPed “+Al4C3” steel reaches 1400 MPa and shows effective strengthening. However, after 1250 °C annealing, the “+Ti3SiC2” and “+Cr2AlC” steels show higher hardness and tensile strength than that of the “+Al4C3” steel. Transmission electron microscopy (TEM) results reveal that nano-particles in the “+Ti3SiC2” and “+Cr2AlC” steels are almost homogenously distributed inside the grains, while for the “+Al4C3” steel, distribution of nano-particles is quite scattered and shows weak connectivity to the matrix. After 1350 °C annealing, all the nano-particles in the three carbide dispersion strengthened steels are almost dissolved into the matrix.