Striations/Fish Boning
Striations are a surface defect characterized by raised parallel ridges in the galvanized coating, which can be caused by the chemical composition of the steel. Striations (left) are related to the type of steel that was galvanized, and while the appearance is affected, the performance of the corrosion protection is not striations are acceptable.
Fish-boning (right) similar to striations, is an irregular pattern over the entire surface of the steel part. Fish boning is caused by differences in the surface chemistry of a large diameter steel piece and variations in the reaction rate between the steel and molten zinc. These surface conditions do not affect the corrosion performance and are acceptable.
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