This paper presents means of improving the chipping resistance of galvannealed steel, as the chipping resistance is important to automotive body panels. Means of coating the upper Fe-rich layer with GA, increasing Al content in the molten zinc bath ad adding a very small quantity of Si to steel are effective in improving of the chipping resistance. Moreover, the addition of Si to steels provides and excellent powdering resistance of GA. These developed GA Steels have been applied practically to the automotive body.
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