Surface-treated steel

Patent metadata

Field	Value
Publication number	US-12104254-B2
Application number	US-202218278429-A
Country	US
Kind code	B2
Filing date	Mar 4, 2022
Priority date	Mar 4, 2021
Publication date	Oct 1, 2024
Grant date	Oct 1, 2024

Abstract

Surface-treated steel including a steel sheet; a plated layer including zinc formed on the steel sheet; and a film formed on the plated layer, the film having a thickness of 100 nm or more and 1000 nm or less, and including an amorphous phase A containing Si, C, O, P, Zn, and V, and one or more selected from the group consisting of Ti, Zr, and Al as constituent elements, with a Zn/Si ratio of peak intensity between Zn and Si, is 1.0 or more, and a mass ratio between V and P, V/P is 0.050 to 1.000 when analyzed by EDS; and an amorphous phase B containing Si, O, and Zn, having a Zn/Si ratio of less than 1.0, and Zn content of the amorphous phase A is 10 mass % or less, when analyzed by EDS.

First claim

What is claimed is:

1. A surface-treated steel comprising:
a steel sheet;
a plated layer including zinc formed on the steel sheet; and
a film formed on the plated layer,
wherein the film has a thickness of 100 nm or more and 1000 nm or less,
wherein the film includes:
an amorphous phase A containing Si, C, O, P, Zn, and V, and one or more selected from the group consisting of Ti, Zr, and Al as constituent elements, wherein Zn/Si, which is a peak intensity ratio between Zn and Si, is 1.0 or more, and V/P, which is a mass ratio between V and P, is 0.050 to 1.000 when analysis is performed by EDS; and
an amorphous phase B containing Si, O, and Zn, wherein the amorphous phase B has a Zn/Si of less than 1.0, the Zn/Si is a peak intensity ratio between Zn and Si when analysis is performed by EDS,
a Zn content of the amorphous phase A is 10 mass % or less, and
in a cross section in a thickness direction, a percentage of a length of an interface between the plated layer and the amorphous phase B to a length of an interface between the plated layer and the film is 30% or more.

2. The surface-treated steel according to claim 1 , wherein
a chemical composition of the plated layer includes, by mass %,
Al: 0.1% or more and less than 25.0%,
Mg: 0% or more and less than 12.5%,
Sn: 0% or more and 20% or less,
Bi: 0% or more and less than 5.0%,
In: 0% or more and less than 2.0%,
Ca: 0% or more and 3.0% or less,
Y: 0% or more and 0.5% or less,
La: 0% or more and less than 0.5%,
Ce: 0% or more and less than 0.5%,
Si: 0% or more and less than 2.5%,
Cr: 0% or more and less than 0.25%,
Ti: 0% or more and less than 0.25%,
Ni: 0% or more and less than 0.25%,
Co: 0% or more and less than 0.25%,
V: 0% or more and less than 0.25%,
Nb: 0% or more and less than 0.25%,
Cu: 0% or more and less than 0.25%,
Mn: 0% or more and less than 0.25%,
Fe: 0% or more and 5.0% or less,
Sr: 0% or more and less than 0.5%,
Sb: 0% or more and less than 0.5%,
Pb: 0% or more and less than 0.5%,
B: 0% or more and less than 0.5%, and
the remainder: Zn and impurities.

Assignees

• Nippon Steel Corp

Inventors

• Yamaguchi Shinichi

Classifications

• C23C28/00

  Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D · CPC title

• C23C22/05 Primary

  using aqueous solutions · CPC title

• C23C2/26

  After-treatment (C23C2/14 takes precedence) · CPC title

• C22C38/00

  Ferrous alloys, e.g. steel alloys (cast-iron alloys C22C37/00) · CPC title

• C22C18/04

  with aluminium as the next major constituent · CPC title