ZN-MG ALLOY PLATED STEEL SHEET HAVING EXCELLENT BLACKENING RESISTANCE AND COATING ADHESION, AND METHOD FOR MANUFACTURING THE SAME

摘要

PURPOSE: A Zn-Mg alloy plated steel sheet having a blackening resistance, and an excellent adhesion, and a method for manufacturing thereof are provided to commercialize as a steel plate material having a highly resistant for a high class surface treat, and as an industry based material capable of using with an economical price to an industry including a vehicle, an electronic, a construction material etc. by preventing a darkening caused by a moisture and by improving an adhesion. CONSTITUTION: A Zn-Mg alloy plated steel sheet having a blackening resistance, and an excellent adhesion comprises a steel substrate, a Zn-Fe inter-metal compound layer, a first Zn-Mg coating layer, a second Zn-Mg coating layer, and an oxide film. The first Zn-Mg coating layer is formed on a Zn-Fe inter-metal compound layer, and includes a Zn-Mg inter-metal compound in which a content of Zn is more than 95 weight%. The second Zn-Mg coating layer is formed on the first Zn-Mg coating layer, and includes the Zn-Mg inter-metal compound in which a content of Zn is 80-95 weight%. The oxide film is formed on the second Zn-Mg coating layer, and comprises a metal oxide. [Reference numerals] (AA) Classification; (BB) Mixed layer of Zn-Mg, Zn and Mg; (CC,FF) Material; (DD) Oxide layer of SiO2 and MgO; (EE) Inter-metal compound layer