High strength anti-atmosphere corrosion steel and production method thereof

Abstract

The invention relates to high-strength atmospheric corrosion resistant steel and a production method thereof, and belongs to the field of metallurgy. The technical problem to be solved by the invention is to provide the high-strength atmospheric corrosion resistant steel of which the yield strength is more than or equal to 550 MPa. The high-strength atmospheric corrosion resistant steel comprises the following chemical compositions in percentage by weight: less than or equal to 0.12 percent of carbon, less than or equal to 0.75 percent of silicon, less than or equal to 1.50 percent of manganese, less than or equal to 0.025 percent of phosphorus, less than or equal to 0.008 percent of sulfur, 0.30 to 1.25 percent of chromium, 0.12 to 0.65 percent of nickel, 0.20 to 0.55 percent of copper, 0.006 to 0.02 percent of titanium, more than 0.09 percent and less than or equal to 0.15 percent of vanadium, 0.01 to 0.02 percent of nitrogen, 0.015 to 0.03 percent of niobium, and the balance of iron and inevitable impurities. The high-strength atmospheric corrosion resistant steel has superior comprehensive properties of high strength, high toughness, high plasticity, obvious yield point and the like, and has wide application prospect.

Description

technical field [0001] The invention relates to high-strength atmospheric corrosion-resistant steel and a production method thereof, belonging to the field of metallurgy. Background technique [0002] The corrosion resistance of atmospheric corrosion-resistant steel is different from that of corrosion-resistant alloys. It is protected by the rust layer formed on the surface of ordinary carbon steel. Copper, phosphorus, chromium, and nickel have always been recognized as the key to improving the atmospheric corrosion resistance of steel. Effective elements, the most representative steel grades are Cu-P-Cr-Ni series with high weather resistance and Cu-Cr-Ni series for welded structures. [0003] At present, "structure strengthening" technologies such as acicular ferrite and ultra-low carbon bainite and "ultra-fine grain" technologies can make the yield strength of atmospheric corrosion-resistant steel reach 500 MPa, but the most economical and feasible method is still For "mi...

AI Technical Summary

Problems solved by technology

The Nb-based microalloying route focuses on strengthening the structure. Therefore, there are disadvantages such as heavy hot rolling load, difficult hot rolling process control, and no obvious yield point phenomenon in the stress-strain curve of the tensile test of the steel.

[0004] The patent application with application number 2008103042956 discloses a high-strength atmospheric corrosion-resistant steel and its production method, but the yield strength of this steel can only reach 500 MPa, which cannot meet the needs of higher-strength atmospheric corrosion-resistant steel