| 摘要 |
PURPOSE: To produce a coated sheet for the can end exhibiting excellent corrosion resistance and capable of suppressing an external flaw by process-annealing and then cold-rolling a cold-rolled sheet freed from a surface flaw and applying coating and baking. CONSTITUTION: A 5052 alloy (Cr alloy contg. 2.5wt.% Al and 0.25wt.% Mg) and a 5182 alloy (Cr alloy contg. 4.45wt.% Al, 0.8% Mg and 0.1wt.% Mn) as the Al-Mg alloy are melted and cast. The ingot is hot-rolled and then cold-rolled. The cold-rolled sheet is then etched with alkali. An alkali soln. at >= pH10 is used to etch the sheet surface by >=0.5μm, and the surface flaw generated in hot rolling is removed. The etched sheet is then process-annealed and cold- rolled to the final thickness. The cold-rolled sheet is coated and baked to obtain the Al-Mg alloy coated sheet for a can end. Consequently, the sheet having the same color tone as that of the conventional one is obtained.
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