Excess Aluminum in Galvanizing Bath
Another type of surface defect, shown in the image to the left, is caused by an excess amount of aluminum in the galvanizing bath. This creates bare spots, seen as black marks, on the surface of the steel. The part may be repaired only if small areas of bare spots are evident. If this condition occurs over the entire part, the part must be rejected, stripped, and regalvanized.
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