Method of preparing a high strength dual phase steel plate with superior toughness and weldability (LAW219)

摘要

A high strength steel composition comprising ferrite and martensite/bainite phases, the ferrite phase having primarily vanadium and niobium carbide or carbonitride precipitates, is prepared by a first rolling above the austenite recrystallization temperature, a second rolling below the austenite recrystallization temperature; cooling between the Ar3 transformation point and 500 DEG C.; and water cooling to below about 400 DEG C.