Аннотация:High-nitrogen steels are promising materials possessing a combination of high properties of strength, ductility and corrosion resistance. However, a powerful and complex equipment is required for the production of high-nitrogen steels by metallurgy methods under high nitrogen pressure. From energy-saving viewpoint, one of alternative and more attractive techniques is aluminothermy or reduction of metal oxides by metallic aluminum. The high temperature synthesis process occurs in this case due to the chemical energy of exothermic oxidation-reduction reaction. In the present work, the microstructure and mechanical properties of high-nitrogen steel 23Cr9Мn1N (wt.%) produced by aluminothermic SHS-metallurgy under nitrogen pressure using thermodynamic modeling are investigated. The melt was saturated with nitrogen simultaneously from the gas phase and chromium nitrides in the charge. As-cast steel has ferrite-austenitic structure with indications of austenite discontinuous decomposition with Cr2N precipitations. The average grain size of the steel is about 16 μm. Forging at T = 1150 – 1170°C of the cast steel leads to a refinement of the structure and increase of the austenite fraction in the steel. After heat treatment of the forged sample (quenching in water from 1200°C), there is a single austenite phase. The analysis of change of austenite FCC lattice parameter in the process of structure evolution under hot plastic deformation and heat treatment is carried out. Investigation of mechanical properties shows a combination of high values of strength and plasticity of steel after quenching. A conclusion is drawn that by aluminothermy one can obtain high-nitrogen steel, which has mechanical properties not worse than those of steel obtained by electroslag remelting under a nitrogen pressure.