Plated steel sheet

Patent metadata

Field	Value
Publication number	US-11634790-B2
Application number	US-202017434988-A
Country	US
Kind code	B2
Filing date	Apr 16, 2020
Priority date	Apr 19, 2019
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A plated steel sheet includes: a steel sheet; and a plating layer that is formed on at least a part of a surface of the steel sheet, in which a chemical composition of the plating layer includes, by mass %, Al: more than 5.00% and 35.00% or less, Mg: 3.00% to 15.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder of Zn and impurities, in which in a cross section of the plating layer in a thickness direction, the area ratio of a lamellar structure in which an (Al—Zn) phase and a MgZn2 phase are arranged in layers is 10% to 90%, a lamellar spacing of the lamellar structure is 2.5 μm or less, and the area ratio of an (Al—Zn) dendrite is 35% or less.

First claim

What is claimed is:

1. A plated steel sheet comprising:
a steel sheet; and
a plating layer that is formed on at least a part of a surface of the steel sheet,
wherein a chemical composition of the plating layer includes, by mass %,
Al: more than 5.00% and 35.00% or less,
Mg: 3.00% to 15.00%,
Si: 0% to 2.00%,
Ca: 0% to 2.00%, and
a remainder of Zn and impurities,
in a cross section of the plating layer in a thickness direction,
an area ratio of a lamellar structure in which an (Al—Zn) phase and a MgZn 2 phase are arranged in layers is 10% to 90%,
a lamellar spacing of the lamellar structure is 2.5 μm or less, and
an area ratio of an (Al—Zn) dendrite is 35% or less.

2. The plated steel sheet according to claim 1 ,
wherein the chemical composition of the plating layer includes, by mass %, one or more kinds of
Al: 11.00% to 30.00%,
Mg: 3.00% to 11.00%, and
Ca: 0.03% to 1.00%.

3. The plated steel sheet according to claim 2 , wherein the chemical composition of the plating layer further includes, by mass %:
Sb: 0.50% or less;
Pb: 0.50% or less;
Cu: 1.00% or less;
Sn: 1.00% or less;
Ti: 1.00% or less;
Sr: 0.50% or less;
Ni: 1.00% or less;
Mn: 1.00% or less; and
Fe: 2.00% or less.

4. The plated steel sheet according to claim 2 ,
wherein in the cross section of the plating layer in the thickness direction, the area ratio of the lamellar structure is 50% to 90%.

5. The plated steel sheet according to claim 2 , further comprising an alloy layer that is provided between the plating layer and the steel sheet and is formed of an Al—Fe-based intermetallic compound having an average thickness of 0.05 μm to 3.0 μm.

6. The plated steel sheet according to claim 2 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the plating layer.

7. The plated steel sheet according to claim 1 , wherein the chemical composition of the plating layer further includes, by mass %:
Sb: 0.50% or less;
Pb: 0.50% or less;
Cu: 1.00% or less;
Sn: 1.00% or less;
Ti: 1.00% or less;
Sr: 0.50% or less;
Ni: 1.00% or less;
Mn: 1.00% or less; and
Fe: 2.00% or less.

8. The plated steel sheet according to claim 7 ,
wherein in the cross section of the plating layer in the thickness direction, the area ratio of the lamellar structure is 50% to 90%.

9. The plated steel sheet according to claim 7 , further comprising an alloy layer that is provided between the plating layer and the steel sheet and is formed of an Al—Fe-based intermetallic compound having an average thickness of 0.05 μm to 3.0 μm.

10. The plated steel sheet according to claim 7 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the plating layer.

11. The plated steel sheet according to claim 1 ,
wherein in the cross section of the plating layer in the thickness direction, the area ratio of the lamellar structure is 50% to 90%.

12. The plated steel sheet according to claim 11 ,
wherein in the cross section of the plating layer in the thickness direction, the area ratio of the lamellar structure is 70% to 90%.

13. The plated steel sheet according to claim 12 , further comprising an alloy layer that is provided between the plating layer and the steel sheet and is formed of an Al—Fe-based intermetallic compound having an average thickness of 0.05 μm to 3.0 μm.

14. The plated steel sheet according to claim 12 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the plating layer.

15. The plated steel sheet according to claim 11 , further comprising an alloy layer that is provided between the plating layer and the steel sheet and is formed of an Al—Fe-based intermetallic compound having an average thickness of 0.05 μm to 3.0 μm.

16. The plated steel sheet according to claim 11 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the plating layer.

17. The plated steel sheet according to claim 1 , further comprising an alloy layer that is provided between the plating layer and the steel sheet and is formed of an Al—Fe-based intermetallic compound having an average thickness of 0.05 μm to 3.0 μm.

18. The plated steel sheet according to claim 17 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the alloy layer.

19. The plated steel sheet according to claim 1 ,
wherein the steel sheet includes an internally oxidized layer that is provided in a surface layer area on an interface side between the steel sheet and the plating layer.

Assignees

• Nippon Steel Corp

Inventors

• Mitsunobu Takuya
• Maki Jun
• Takebayashi Hiroshi
• Takahashi Takehiro
• Tokuda Kohei

Classifications

• C23C2/29

  Cooling or quenching · CPC title

• C23C2/26

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

• C23C2/0224

  Two or more thermal pretreatments · CPC title

• C23C2/0222

  in a reactive atmosphere, e.g. oxidising or reducing atmosphere (C23C2/024 takes precedence) · CPC title

• Y10T428/12667

  Oxide of transition metal or Al · CPC title