| 摘要 |
PURPOSE:To form a glass film having high tension and superior adhesion by coating a cold rolled steel sheet with an aqueous soln. of an Mn compound and diffusing Mn in the surface of the steel sheet by annealing in hydrogen. CONSTITUTION:The surface of a cold rolled steel sheet is coated with an aqueous soln. or dispersion of an Mn compound after final cold rolling so that Mn is present on the surface of the steel sheet by 0.1-1g/m<2>. The steel sheet is dried in the air, annealed in a hydrogen atmosphere, and subjected to decarburization annealing, coating with a protective coating material for annealing and finish annealing as usual. Mn(NO3)2 or Mn(H2PO4)2 is used as the Mn compound. |
