| 摘要 |
PURPOSE:To reduce steps of a process and labor by cold rolling a steel plate directly with adhering scales and making box annealing in the atmosphere of nonreducing gas and thereby enabling easy removing of scales. CONSTITUTION:A hot rolled steel plate carrying adhered scales is directly cold rolled at a rolling reduction of 70% to obtain a steel plate covered with black fine powdery scales. This is box annealed in the nonreducing atmosphere, for instance gaseous N2 etc., and cooled in the furnace. Scales adhered to the surface of the cooled steel plate can be removed easily by the drive thrust method and the liquid honing method. The steel plate made rolled free from scales is excellent in cleanness of the surface and adherence of coating. |
