| 摘要 |
PURPOSE:To increase welding quality without decrease in corrosion resistance by forming an outer can and a cover with a cold rolled steel plate whose both surfaces are previously nickel-plated, then by cutting the welding surface. CONSTITUTION:A cover 3 and an outer can 4 made of a cold rolled steel plate whose both surfaces are nickel-plated are used. Since the cold rolled steel plate is nickel plated before forming, the thickness of nickel plating is uniform compared with barrel plating after forming and sufficient corrosion resistance can be obtained in minimum thickness. The nickel plated cold rolled steel plate is formed in the outer can, then the outer can is cut off from the steel plate. No nickel plated layer exists on the cut surface 5. The amount of nickel in the welded part is decreased and welding yield is increased. |
