BATTERY CAN MATERIAL EXCELLENT IN DEEP DRAWABILITY AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a battery can material small in a secular change of contact electric resistance and excellent in deep drawability. SOLUTION: This battery can material is the one using a cold rolled steel sheet as a substrate and is provided with an Ni-Fe diffused layer formed on both sides thereof and an Ni-Cu diffused layer contg. 5 to 40wt.% Cu and formed on the face equivalent to the outer face of the battery can. It is produced in such a manner that both sides of the cold rolled steel sheet are applied with Ni plating, furthermore, Cu plating is applied to the surface of the Ni plating on the side equivalent to the outer face of the battery can, which is thereafter subjected to heating diffusing treatment by continuous annealing or box type annealing. As for the continuous annealing, the conditions of heating of 700 to 900 deg.C for 30sec to 2min are adopted. As for the box type annealing, the conditions of heating at 500 to 800 deg.C for 5 to 8hr are adopted.