Abstract: Microstructure of the 00Cr23Ni12Mn5Mo2N austenitic stainless steel under different preparation processes, as well as the mechanical properties and fracture morphology of the surface and core after high temperature homogenization, were studied by means of optical microscope, scanning electron microscope, tensile testing machine and impact testing machine. The results demonstrate that high temperature homogenization at 1190 ℃ for 24 h can effectively eliminate the σ-phase, effectively improve the high temperature properties of the tested steel and provide favorable conditions for forging. After high temperature homogenization, by forging and forming with two upsetting and two drawing methods, and controlling the forging temperature between 1210-950 ℃, the problem of insufficient deformation of the core can be effectively solved, the dynamic recrystallization of surface and core is complete, the microstructure is uniform and fine and the grain size of the surface and core can both reach grade 6 or above. The surface and core properties after forging are excellent. The tensile strength, elongation, percentage reduction of area, hardness and impact absorbed energy at 77 K on surface of the tested steel are 821 MPa, 41.0%, 65.0%, 252 HBW and 49.1 J, respectively, while the strength and hardness of the core are slightly lower than that of the surface, and the plasticity and toughness of the core are better.

Key words: 00Cr23Ni12Mn5Mo2N austenitic stainless steel, high temperature homogenization, microstructure, mechanical properties