Hot-rolled dual-phase steel in 590MPa tensile strength grade and method for manufacturing hot-rolled dual-phase steel

The present invention discloses a hot rolled dual phase steel tensile strength of 590MPa and a manufacturing method. The steel chemical composition by weight percent of: C: 0.04 ~ 0.10%, Mn: 1.10 ~ 1.50%, Si: 0.10 ~ 0.20%, Als: 0.015 ~ 0.070%, P: 0.03 ~ 0.08%, S≤0.008% , Cr: 0.5 ~ 1.2%, the balance being Fe and unavoidable impurities. The method for producing the steel comprises hot metal desulfurization, smelting, vacuum processing, casting, finishing, heating the slab, hot rolling, laminar cooling, coiling step. Practice has proved that the steel having high tensile strength and low yield ratio and excellent cold forming and fatigue resistance, and a method of manufacturing process is simple, production cost is low.