Surface-treated steel sheet and method for manufacturing surface-treated steel sheet

Patent metadata

Field	Value
Publication number	US-11794449-B2
Application number	US-201917253322-A
Country	US
Kind code	B2
Filing date	Jul 5, 2019
Priority date	Jul 6, 2018
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

A surface-treated steel sheet of the present invention includes a base steel sheet and a Ni—Co—Fe alloy-plated layer on at least one surface of the base steel sheet, in which, in the alloy-plated layer, a Ni coating weight is 7.1 to 32.5 g/m2, a Co coating weight is 0.65 to 5.2 g/m2, and a total of the Ni coating weight and the Co coating weight is in a range of 9.0 to 35.0 g/m2. In an outermost layer of the alloy-plated layer, a Co concentration is in a range of 20 to 60 atom %, and a Fe concentration is in a range of 5 to 30 atom %. In the alloy-plated layer, a region having a thickness of 2 μm or more, in which a total of a Ni concentration and the Co concentration is 10 atom % or more and the Fe concentration is 5 atom % or more, is present, and the base steel sheet has a predetermined chemical composition, and a ferrite grain size number is 9.0 or more.

First claim

The invention claimed is:

1. A surface-treated steel sheet, comprising:
a base steel sheet; and
a Ni—Co—Fe alloy-plated layer positioned on at least one surface of the base steel sheet,
wherein, in the Ni—Co—Fe alloy-plated layer, a Ni coating weight is in a range of 7.1 to 32.5 g/m 2 , a Co coating weight is in a range of 0.65 to 5.2 g/m 2 , and furthermore, a total of the Ni coating weight and the Co coating weight is in a range of 9.0 to 35.0 g/m 2 ,
in an outermost layer of the Ni—Co—Fe alloy-plated layer, a Co concentration is in a range of 20 to 60 atom %, and a Fe concentration is in a range of 5 to 30 atom %,
in the Ni—Co—Fe alloy-plated layer, a region having a thickness of 2 μm or more, where a total of a Ni concentration and the Co concentration is 10 atom % or more and the Fe concentration is 5 atom % or more, is present,
a chemical composition of the base steel sheet includes, by mass %,
C: 0.001% to 0.020%,
Si: 0.1% or less,
Mn: 0.05% to 0.90%,
P: 0.025% or less,
S: 0.025% or less,
sol. Al: 0.003% to 0.100%,
N: 0.007% or less, and
B: 0% to 0.0050%,
the chemical composition further includes
at least any one of 0.1% or less of Ti and 0.12% or less of Nb such that a relationship represented by Expression (1) is satisfied, a remainder consists of Fe and an impurity, and
a ferrite grain size number of the base steel sheet, specified by JIS G 0551 (2013), is 9.0 or more,
(C/12+N/14)<(Ti/48+Nb/93)+0.001  Expression (1)

in Expression (1), C, N, Ti, and Nb represent contents (unit: mass %) of each of the elements.

2. The surface-treated steel sheet according to claim 1 ,
wherein, in the outermost layer of the Ni—Co—Fe alloy-plated layer, a total of the Fe concentration and the Co concentration is 65 atom % or less, and the Co concentration is higher than the Fe concentration.

3. The surface-treated steel sheet according to claim 2 ,
wherein, in the Ni—Co—Fe alloy-plated layer, a ratio of the Co coating weight to the Ni coating weight is in a range of 0.05 to 0.27.

4. The surface-treated steel sheet according to claim 1 ,
wherein the ferrite grain size number of the base steel sheet is 10 or more.

5. The surface-treated steel sheet according to claim 4 ,
wherein, in the Ni—Co—Fe alloy-plated layer, a ratio of the Co coating weight to the Ni coating weight is in a range of 0.05 to 0.27.

6. The surface-treated steel sheet according to claim 1 ,
wherein, in the Ni—Co—Fe alloy-plated layer, a ratio of the Co coating weight to the Ni coating weight is in a range of 0.05 to 0.27.

7. The surface-treated steel sheet according to claim 1 ,
wherein the surface-treated steel sheet is used for a battery can.

8. The surface-treated steel sheet according to claim 1 ,
wherein the surface-treated steel sheet is used for a positive electrode current collector of a battery having an alkaline aqueous solution used as an electrolytic solution.

9. The surface-treated steel sheet according to claim 1 ,
wherein the Co coating weight is in a range of 0.9 to 5.2 g/m 2 .

10. A method for manufacturing a surface-treated steel sheet, the method comprising:
carrying out Ni plating on a steel sheet having the chemical composition of the base steel sheet according to claim 1 using a Ni plating bath having a chloride ion concentration of 35 g/L or more;
carrying out Co plating on the steel sheet; and
carrying out an alloying treatment on the steel sheet.

11. A surface-treated steel sheet, comprising:
a base steel sheet; and
a Ni—Co—Fe alloy-plated layer positioned on at least one surface of the base steel sheet,
wherein, in the Ni—Co—Fe alloy-plated layer, a Ni coating weight is in a range of 7.1 to 32.5 g/m 2 , a Co coating weight is in a range of 0.65 to 5.2 g/m 2 , and furthermore, a total of the Ni coating weight and the Co coating weight is in a range of 9.0 to 35.0 g/m 2 ,
in an outermost layer of the Ni—Co—Fe alloy-plated layer, a Co concentration is in a range of 20 to 60 atom %, and a Fe concentration is in a range of 5 to 30 atom %,
in the Ni—Co—Fe alloy-plated layer, a region having a thickness of 2 μm or more, where a total of a Ni concentration and the Co concentration is 10 atom % or more and the Fe concentration is 5 atom % or more, is present,
a chemical composition of the base steel sheet includes, by mass %,
C: 0.001% to 0.020%,
Si: 0.1% or less,
Mn: 0.05% to 0.90%,
P: 0.025% or less,
S: 0.025% or less,
sol. Al: 0.003% to 0.100%,
N: 0.007% or less, and
B: 0% to 0.0050%,
the chemical composition further includes
at least any one of 0.1% or less of Ti and 0.12% or less of Nb such that a relationship represented by Expression (1) is satisfied, a remainder comprising Fe and an impurity, and
a ferrite grain size number of the base steel sheet, specified by JIS G 0551 (2013), is 9.0 or more,
(C/12+N/14)<(Ti/48+Nb/93)+0.001  Expression (1)

in Expression (1), C, N, Ti, and Nb represent contents (unit: mass %) of each of the elements.

Assignees

• Nippon Steel Corp

Inventors

• Takahashi Takehiro
• Saito Mamoru
• Ishizuka Kiyokazu
• Goto Yasuto

Classifications

• C21D8/00

  Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation C21D1/02) · CPC title

• B32B15/013 Primary

  one layer being formed of an iron alloy or steel, another layer being formed of a metal other than iron or aluminium · CPC title

• C21D8/005

  Chemistry & Metallurgy · mapped topic

• C21D8/0236

  Cold rolling · CPC title

• C22C38/02

  containing silicon · CPC title