Patent ID: 11946121
Assignee: JFE STEEL CORPORATION
Field: Materials, metallurgy (Chemistry)
Classification: CPC C  H  Y | IPC C  H

Claim 2:
3. A battery outer tube can, comprising:
an Fe—Ni diffusion layer on each of an inner surface and an outer surface of a steel sheet formed in a shape of a battery outer tube can; and
further a Ni layer on the Fe—Ni diffusion layer on the outer surface of the steel sheet,
wherein the steel sheet has a composition consisting of, by mass, C in an amount of not more than 0.010%, Si in amount of not more than 0.02%, Mn in an amount of not more than 0.60%, P in an amount of not more than 0.020%, S in an amount of not more than 0.020%, Ni in an amount of not more than 0.05%, N in an amount of not more than 0.0050%, Nb in an amount of not less than 0.010% and not more than 0.050%, and Cr in an amount of more than 0 mass % and not more than 1.0%, with the balance being Fe and inevitable impurities,
part of the Fe—Ni diffusion layer on the outer surface of the steel sheet constitutes an Fe—Ni diffusion layer A having a deposition amount of not less than 50 mg/m2 and not more than 500 mg/m2 in terms of an amount of Ni per one surface of the steel sheet,
a proportion of Ni at an outermost surface of the Fe—Ni diffusion layer is not less than 1.0% and less than 20.0%, and
the proportion of Ni is a proportion of the amount of Ni in a total amount of Fe and Ni at the outermost surface of the Fe—Ni diffusion layer, and a unit of the amount of Fe and the amount of Ni is at %.