Hot-dip zn-alloy-plated steel sheet and method for producing same

Patent metadata

Field	Value
Publication number	US-2016281201-A1
Application number	US-201415037489-A
Country	US
Kind code	A1
Filing date	Nov 13, 2014
Priority date	Dec 3, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

This hot-dip Zn-alloy-plated steel sheet comprises: a steel sheet; and a hot-dip Zn-alloy-plated layer arranged on a surface of the steel sheet. The entire surface of the hot-dip Zn-alloy-plated layer satisfies the following formula (1): S[Zn(OH) 2 ]/(S[Zn(OH) 2 ]+S[Zn])×100≦40. In formula (1): S[Zn] is the area exhibited by a peak having a center at approximately 1022 eV ascribable to metallic Zn in an intensity profile in XPS analysis of the surface of the hot-dip Zn-alloy-plated layer; and S[Zn(OH) 2 ] is the area exhibited by a peak having a center at approximately 1023 eV ascribable to Zn(OH) 2 in an intensity profile in XPS analysis of the surface of the hot-dip Zn-alloy-plated layer.

First claim

1 . A hot-dip Zn alloy-plated steel sheet comprising:
a steel sheet; and a hot-dip Zn alloy plating layer disposed on a surface of the steel sheet, wherein the hot-dip Zn alloy plating layer satisfies, at a whole of a surface of the hot-dip Zn alloy plating layer, following Equation 1:

S


[

Zn


(
OH
)

2

]

S


[

Zn


(
OH
)

2

]

+

S


[
Zn
]

×
100

≤
40

(

Equation



1

)

S[Zn] is a peak area derived from metal Zn and centered at approximately 1022 eV in an intensity profile of XPS analysis of the surface of the hot-dip Zn alloy plating layer; and S[Zn(OH) 2 ] is a peak area derived from Zn(OH) 2 and centered at approximately 1023 eV in the intensity profile of XPS analysis of the surface of the hot-dip Zn alloy plating layer.

2 . The hot-dip Zn alloy-plated steel sheet according to claim 1 , wherein:
the hot-dip Zn alloy plating layer comprises 1.0 to 22.0% by mass of Al, 0.1 to 10.0% by mass of Mg, and the balance of the hot-dip Zn alloy plating layer being Zn and unavoidable impurities.

3 . The hot-dip Zn alloy-plated steel sheet according to claim 2 , wherein:
the hot-dip Zn alloy plating layer further comprises at least one selected from the group consisting of 0.001 to 2.0% by mass of Si, 0.001 to 0.1% by mass of Ti, and 0.001 to 0.045% by mass of B.

4 . A method of producing a hot-dip Zn alloy-plated steel sheet comprising:
dipping a base steel sheet in a hot-dip Zn alloy plating bath to form a hot-dip Zn alloy plating layer on a surface of the base steel sheet; and contacting an aqueous solution containing a water-soluble corrosion inhibitor with a surface of the hot-dip Zn alloy plating layer to cool the base steel sheet and the hot-dip Zn alloy plating layer having a raised temperature through formation of the hot-dip Zn alloy plating layer, wherein a temperature of the surface of the hot-dip Zn alloy plating layer when the aqueous solution is to be contacted with the surface of the hot-dip Zn alloy plating layer is equal to or more than 100° C. and equal to or less than a solidifying point of the plating layer; and wherein the aqueous solution containing the water-soluble corrosion inhibitor satisfies following Equation 2:

Z
0

-

Z
1

Z
0

×
100

≥
20

(

Equation



2

)

Z 0 is a corrosion current density of the hot-dip Zn alloy-plated steel sheet measured in a 0.5 M NaCl aqueous solution not containing the water-soluble corrosion inhibitor, and Z 1 is a corrosion current density of the hot-dip Zn alloy-plated steel sheet measured in the aqueous solution containing the water-soluble corrosion inhibitor, in which NaCl is further dissolved so that a final concentration of NaCl is 0.5 M.

Assignees

• Nisshin Steel Co Ltd

Inventors

• Shimizu Atsuo
• Matsuno Masanori
• Yamamoto Masaya
• Taketsu Hirofumi

Classifications

• C22C18/04

  with aluminium as the next major constituent · CPC title

• C22C21/10

  with zinc as the next major constituent · CPC title

• C22C18/00 Primary

  Alloys based on zinc · CPC title

• C23C2/12 Primary

  Aluminium or alloys based thereon · CPC title

• C23C18/48

  Coating with alloys · CPC title