METHOD FOR PRODUCTION OF HOT-ROLLED STEEL PRODUCTS FROM TOOL STEEL Russian patent published in 2021 - IPC C21D8/02 C22C38/28 C22C38/50 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of ferrous metallurgy, namely to the production of high-strength sheet metal for high-precision machine-building equipment. Steel is melted with the following chemical composition, wt. %: carbon 0.4-0.8, silicon 0.4-1.2, manganese 0.1-0.7, sulfur no more than 0.03, phosphorus no more than 0.03, chromium 0.7-1.5, nickel 0.001-0.5, copper 0.001-0.04, nitrogen no more than 0.012, vanadium 0.001-0.2, titanium 0.001-0.15, molybdenum 0.001-0.3, tungsten no more than 0.2 with its subsequent casting. Hot rolling with a total compression of at least 88% at the temperature of its beginning 1110-1200°C is performed and finished at a temperature of 830-930°C. After that, the sheets are placed in a furnace heated to a temperature of 790-840°C, exposure is carried out for 20-50 minutes, then the temperature is lowered to 740-800°C and the exposure is carried out for another 20-50 minutes, and then the sheets are cooled in air.

EFFECT: reduction in the tendency of steel to crack during quenching is achieved, an increase in the strength and viscosity of steel after final heat treatment, as well as ensuring uniform hardness across the section of rolled metal.

4 cl, 2 tbl, 1 ex