Effect of hot-rolling and heat-treatment conditions on the structure and mechanical and technological properties of nitrogen-bearing austenitic steel 05Kh22AG15N8M2F-Sh

Abstract

The effect of hot-rolling conditions on the structure, strength, ductility, fracture toughness, and technological properties of the nonmagnetic steel 05Kh22AG15N8M2F-Sh containing 0.55% N has been studied. A homogeneous and fine-grained austenitic structure forms in the steel upon rolling at 1000–1050°C and a reduction of more than 60–70%. This structure provides the following properties: σ0.2 = 1044 N/mm2, σu = 1172 N/mm2, δ = 32%, ψ = 64%, and KCV = 1.06 MJ/m2 at −70°C. The possibility of recrystallization of the hot-rolled steel (deformed at 10–90% reductions) is checked upon its subsequent heating to 850–1200°C followed by water quenching. The steel is shown to have high strength, ductility, and fracture toughness and to retain an austenitic structure without cracks or exfoliation upon hot plastic deformation by rolling up to a 90% reduction.