HOT-DIP GALVANIZED HIGH STRENGTH STEEL WITH HIGH STRAIN HARDENING INDEX AND METHOD PRODUCING SAME

摘要

A hot-dip galvanized high strength steel consists of (wt.%): C：0.11-0.20，Al：0.51-1.22，Mn：1.50-2.00，Si：0.07-0.30，Cr：1.0-2.0，P≤0.015，S≤0.015, and the balance of iron and unavoidable impurities. A method for producing the same comprises the following steps: smelting and continuous casting into billet; heating the continuous cast billet and preserving heat; rough rolling; final rolling; winding up; cold rolling; and hot-dip galvanizing, i.e. heating the cold rolled steel plate, preserving heat, rapid cooling to the temperature of 480-510℃, dip galvanizing for 5-9 seconds, and then cooling to room temperature. The hot-dip galvanized high strength steel has the characteristics of good galvanizability, high tensile property and good welding performance, corrosion resistance and formability.