Patent ID: 11453934

Abstract:
The present invention relates to high-strength high-toughness low-temperature thick-plate structural steel and a heat treatment method thereof. The steel is composed of the following components by weight percentage: C: 0.03-0.08%, Cr: 0.8-1.9%, Mn: 0.01-1.0%, Ni: 3.5-7%, Mo: 0.2-0.5%, V: 0.15-0.2%, Nb: 0.01-0.05%, Cu: 1.2-3.8%, Al: 0-0.5%, P: <0.015%, S: <0.010%, and Fe and inevitable impurities as balance. Compared with the prior art, a steel plate prepared in the present invention can be used at low temperature of −20 to −120° C. and −196° C., maintains relatively high strength and certain toughness, and mainly resolves a technical problem that existing high-strength high-toughness quenched and tempered steel cannot meet equipment requirements in polar resource and energy development; transportation, etc.