摘要 |
A method of removing iron oxide scale and coating sheet metal bonds a pre-paint to a wustite layer of the sheet metal. The iron oxide scale on the sheet metal generally comprises three layers prior to surface conditioning: a wustite layer, a magnetite layer, and a hematite layer. The wustite layer is bonded to a base metal substrate of the sheet metal. The magnetite layer is bonded to the wustite layer, and the hematite layer is bonded to the magnetite layer. Conditioning the surface of the sheet metal includes bringing a surface conditioning member into engagement with the surface of the sheet metal in a manner to remove substantially all of the hematite and magnetite layers from the surface, and in a manner to remove some but not all of the wustite layer from the surface. The portion of the wustite layer that remains bonded to the base metal substrate of the sheet metal protects the surface from oxidation until the surface is coated.
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