METHOD FOR MANUFACTURING HOT DIP ALUMINIUM COATED STEEL SHEET WITH SUPERIOR SELF-SACRIFICING CORROSION RESISTANCE AND HOT DIP ALUMINIUM COATABILITY

摘要

The present invention relates to a manufacturing method of a molten aluminum-plated steel sheet, and is comprised of the following steps: preparing a molten aluminum plating bath; and immersing a plated steel sheet containing at least 0.5% by weight in total of more than one selected from the group consisting of Si, Mn and Al in the molten aluminum plating bath. The step of preparing the molten aluminum plating bath includes: melting aluminum ingots to form aluminum molten metal; and controlling a sum of contents of the trace elements in the aluminum molten metal exceeds 0.1 wt% by feeding an Fe-based alloy ingot containing one kind of trace element selected from a group consisting of Li, K, Ca, Na and Mg into the aluminum molten metal.