| 摘要 |
PURPOSE:To improve phosphatability and paint adhesion by pickling the non- plated surface of a steel plate galvanized on one side then rubbing the surface thereby flattening the surface and removing some residual oxides surely. CONSTITUTION:The oxides of the non-plated surface of a steel plate galvanized on one side are removed by dipping said steel plate in aq. solns. of hydrochloric acid, sulfuric acid, etc. or electrolyzing the same. The non-plated surface is rubbed with metallic brushes, nylon brushes contg. abrasive grains, etc., whereby some oxides remaining on the surface are removed and the surface is flattened. As a result, the phosphatability and paint adhesion of the non-plated surface are improved. This method is particularly effective for the galvanized steel plates of which the galvanized surface is subjected to an iron-zinc alloying treatment by heating the same in an alloying furnace after the plating and of which the non-plated surface is formed thereon with many oxides. |
