Cold-base high-strength galvanized sheet and production method thereof

The invention discloses a cold-base high-strength galvanized sheet and a production method thereof, and belongs to the technical field of metallurgical sheet production. The invention aims to provide a cold-base high-strength galvanized sheet with certain extension requirement which is made of a common C-Mn component cold-rolled plate, and a production method, and reduce the production cost. The cold-base high-strength galvanized sheet comprises the following chemical compositions: 0.17 to 0.23 percent of C, 0.65 to 0.85 percent of Mn, less than or equal to 0.15 percent of Si, less than or equal to 0.015 percent of P, less than or equal to 0.012 percent of S, 0.015 to 0.030 percent of Als and the balance of Fe. By optimizing a composition design, adjusting and optimizing process parameters of hot rolling, cold rolling and hot galvanizing procedures, and not adding microalloy elements, the high strength is ensured, the extensibility of the product is improved, the production cost can be obviously reduced, and the safety of using materials is improved. Through detection, the product has the yield strength of 420 to 650MPa, the tensile strength of 550 to 700MPa and the elongation of 9 to 24 percent.