METHOD OF PRODUCING HIGH-STRENGTH COLD-RESISTANT SHEET FROM LOW-ALLOY STEEL Russian patent published in 2018 - IPC C21D8/02 C22C38/00 

FIELD: technological processes.

SUBSTANCE: invention relates to the production of high-strength cold-resistant sheet steel from low-alloy steel with high cold resistance for transport and heavy engineering. Smelt steel of the following composition, wt. %: carbon (0.16–0.27), silicon (0.33–0.62), manganese (1.30–1.90), molybdenum (0.01–0.30), aluminum (0.02–0.07), chromium (not more than 0.15), nickel (not more than 0.15), copper (not more than 0.10), titanium (0.001–0.015), vanadium (0.001–0.01), niobium (0.001–0.008), boron (0.001–0.005), nitrogen (0.001–0.008), sulfur (not more than 0.005), phosphorus (not more than 0.012), iron – the rest. Continuous casting of steel into slabs is produced as well, along with their heating in the temperature range of 1,180–1,250 °C, multipass hot rolling of sheets with an end temperature from 860 to 980 °C, quenching with water at a temperature of 920–970 °C followed by a holiday at a temperature of 500–650 °C.

EFFECT: obtaining economically alloyed sheet metal with enhanced cold resistance and crack resistance while maintaining a sufficient level of strength and plastic properties.

1 cl, 4 tbl