METHOD FOR MANUFACTURING OF Zn-Al ALLOY COATED STEEL PLATE FOR MUFFLER IN VEHICLE WHICH HAS EXCELLENT HEAT RESISTANCE AND ANTI-CORROSION PROPERTY BY USING DOUBLE ALLOY COATED LAYER

摘要

PURPOSE: Provided is a method of production of Zn-Al alloy coated steel plate used for muffler in vehicle, which has excellent heat resistance and anti-corrosion by using double alloy coated layer, and increased life by sacrifice manner on destruction of coated layer. CONSTITUTION: The method comprises the steps of compressing zinc foil(11) and aluminum foil(12) to cold rolled steel in order in clad manner, and passing it through an oven(30) in the range of 300 to 400 deg.C. In contact area of zinc and cold rolled steel is formed GA(GalvAnnealed) alloy coated layer of zinc-iron alloy coated layer by the diffusion of zinc and iron, and in contact area of zinc and aluminum is formed Galvalume alloy coated layer of zinc-aluminum alloy coated layer. The Galvalume alloy coated layer has 3 to 6 times larger anti-corrosion property than zinc coated steel.