Patent ID: 9382630
Filing Date: 2016-07-05
CPC Classification: C23C,Y10T

Claim Text:
1. A process of manufacturing a zinc alloy coated steel sheet having good sealer adhesion and corrosion resistance, the method comprising: depositing a zinc/metal alloy coating layer onto a zinc coated steel sheet of an electro-galvanized steel sheet or a hot-dip galvanized steel sheet to form a layered coating where the zinc/metal alloy coating layer is present at an outermost surface of the coating; and thermally treating the zinc coated steel sheet having the layered coating with the zinc/metal alloy coating layer at the outermost surface at a temperature from 250 degrees Celsius (° C.) or above to less than 300° C. for 3 to 100 seconds, wherein depositing the zinc/metal alloy coating layer is carried out with an alloy material composed of 90-95% by weight of at least one conductive metal selected from the group consisting of Mg, Al, Mn, Cr, Cu, Ti, and Ni, and 5-10% by weight of Zn in a vacuum chamber by using a physical vapor deposition (PVD) method using an electrostatic levitator, and the zinc/metal alloy coating layer has a gradient zinc content decreasing from a surface of the zinc coated steel sheet, wherein, the thermally treated zinc alloy coated steel sheet comprises a zinc coating layer formed on a steel sheet and a zinc/metal alloy layer formed by the diffusion of the metal on the zinc coating layer, and a zinc/iron alloy phase is not present in an interface between the steel sheet and the zinc coating layer.