METHOD OF THERMAL DEFORMATION TREATMENT OF HIGH-STRENGTH COBALT-FREE MARAGING STEEL Russian patent published in 2024 - IPC C21D8/00 C21D1/02 C21D1/22 C21D6/02 

FIELD: metallurgy.

SUBSTANCE: invention relates to a method for thermal deformation production of forgings from high-strength sparingly alloyed cobalt-free maraging steel ChS5U. Method of thermal deformation manufacturing of forged piece from high-strength cobalt-free maraging steel ChS5U includes heating of forged workpiece, hot deformation with subsequent quenching in water and heat treatment with quenching and aging, wherein hot deformation is carried out by rolling heated to 1100°C forged workpiece with completion of rolling to size in temperature range of 950–850°C with provision of steel deformation degree of 22–25% and subsequent quenching in water, wherein total time from completion of rolling and to immersion in water is not more than 5 minutes, which creates phase-hardened austenite with high density of dislocations, which are inherited during quenching by martensite, and heat treatment is carried out in two stages: first heat treatment of the workpiece is carried out at temperature of 940–960°C for 1–1.5 hours, followed by quenching in water, and the second heat treatment of the workpiece is carried out at temperature of 810–830°C for 1–1.5 hours with subsequent quenching in water and aging at 490–510°C for 3 hours.

EFFECT: ensuring stable implementation of strength requirements, as well as plasticity and viscosity in production of rolled rings from cobalt-free maraging steel ChS5U(015N18M4TYU).

1 cl, 1 ex