1200MPa-grade cold-rolled hot-galvanized dual-phase steel and preparation method thereof

The invention relates to the technical field of metal materials, in particular to 1200MPa-grade cold-rolled hot-galvanized dual-phase steel and a preparation method thereof. The method comprises the following steps: pre-plating metal on at least part of the surface of chilled strip steel with set chemical components, and controlling the pre-plating temperature to obtain pre-plated steel; wherein the metal comprises any one of nickel, iron and copper. The pre-plated steel is subjected to continuous annealing; wherein the continuous annealing comprises the following steps: soaking the pre-plated steel, and controlling the soaking temperature; and the pre-plated steel obtained after soaking is subjected to staged cooling and aging and then galvanized, and the cold-rolled hot-galvanized dual-phase steel is obtained. The technical problem that the existing cold-rolled hot-galvanized dual-phase steel is difficult to give consideration to excellent mechanical properties and high hole expansion rate at the same time