High strength dual phase steel plate with superior toughness and weldability

摘要

A high strength steel composition comprising ferrite and martensite/banite phases, the ferrite phase having primarily vanadium and mobium carbide or carbonitride precipitates, is prepared by a first rolling above the austenite recrystallization temperature; a second rolling below the anstenite recrystallization temperature; a third rolling between the Ar3 and Ar1 transformation points, and water cooling to below about 400 DEG C.