Fe-based electroplated steel sheet, hot-dip galvanized steel sheet, and methods for manufacturing same

Patent metadata

Field	Value
Publication number	US-2024271256-A1
Application number	US-202218289928-A
Country	US
Kind code	A1
Filing date	May 17, 2022
Priority date	May 17, 2021
Publication date	Aug 15, 2024
Grant date	—

Abstract

A base steel sheet containing Si in an amount of 0.50 to 3.00 mass % is subjected to an Fe-based electroplating treatment using an Fe-based electroplating solution containing Fe ions and transition metal ions other than the Fe ions to form an Fe-based electroplated layer, and then to an annealing treatment. In the Fe-based electroplating solution, a content of the Fe ions is 1.0 mass % or more and a content of the transition metal ions is 10 to 1000 mass ppm. A coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 1.0 g/m 2 or more. Thus, a steel sheet having high strength and excellent resistance to resistance-weld cracking of a welded portion is obtained.

First claim

1 . A method for producing an Fe-based electroplated steel sheet, the method comprising:
subjecting a base steel sheet containing Si in an amount of 0.50 to 3.00 mass % to an Fe-based electroplating treatment using an Fe-based electroplating solution containing Fe ions and transition metal ions other than the Fe ions to form an Fe-based electroplated layer, and then subjecting the base steel sheet to an annealing treatment, wherein, in the Fe-based electroplating solution, a content of the Fe ions is 1.0 mass % or more and a content of the transition metal ions is 10 to 1000 mass ppm, and a coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 1.0 g/m 2 or more.

2 . The method for producing an Fe-based electroplated steel sheet according to claim 1 ,
wherein the base steel sheet has a chemical composition containing, Si in an amount of 0.50 mass % or more and 3.00 mass % or less, C in an amount of 0.80 mass % or less, Mn in an amount of 1.50 mass % or more and 3.50 mass % or less, P in an amount of 0.100 mass % or less, S in an amount of 0.0300 mass % or less, and Al in an amount of 0.100 mass % or less, with a remaining part consisting of Fe and inevitable impurities.

3 . The method for producing an Fe-based electroplated steel sheet according to claim 2 ,
wherein the chemical composition further contains at least one element selected from the group consisting of: B in an amount of 0.0050 mass % or less, Ti in an amount of 0.200 mass % or less, N in an amount of 0.0100 mass % or less, Cr in an amount of 1.000 mass % or less, Cu in an amount of 1.000 mass % or less, Ni in an amount of 1.000 mass % or less, Mo in an amount of 1.000 mass % or less, Nb in an amount of 0.200 mass % or less, V in an amount of 0.500 mass % or less, Sb in an amount of 0.200 mass % or less, Ta in an amount of 0.100 mass % or less, W in an amount of 0.500 mass % or less, Zr in an amount of 0.1000 mass % or less, Sn in an amount of 0.200 mass % or less, Ca in an amount of 0.0050 mass % or less, Mg in an amount of 0.0050 mass % or less, and REM in an amount of 0.0050 mass % or less.

4 . The method for producing an Fe-based electroplated steel sheet according to claim 1 , wherein the transition metal ions contained in the Fe-based electroplating solution are ions of at least one transition metal selected from the group consisting of Ti, V, Cr, Mn, Ni, Cu, Nb, Mo, and W.

5 . The method for producing an Fe-based electroplated steel sheet according to claim 1 , wherein a coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 5.0 to 20.0 g/m 2 .

6 . A method for producing a hot-dip galvanized steel sheet, the method comprising subjecting an Fe-based electroplated steel sheet obtained by the method according to claim 1 to a hot-dip galvanizing treatment.

7 . The method for producing a hot-dip galvanized steel sheet according to claim 6 , further comprising subjecting the Fe-based electroplated steel sheet to an alloying treatment after the hot-dip galvanizing treatment.

8 . An Fe-based electroplated steel sheet comprising:
a base steel sheet containing Si in an amount of 0.50 to 3.00 mass %; and an Fe-based electroplated layer disposed on at least one surface of the base steel sheet, wherein a coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 1.0 g/m 2 or more, an average crystal grain size of the Fe-based electroplated layer at an interface between the Fe-based electroplated layer and the base steel sheet is 1.00 μm or less, the Fe-based electroplated layer contains a transition metal other than Fe, and a content of the transition metal in the Fe-based electroplated layer is 100 to 10000 mass ppm.

9 . The Fe-based electroplated steel sheet according to claim 8 , wherein the transition metal is at least one transition metal selected from the group consisting of Ti, V, Cr, Mn, Ni, Cu, Nb, Mo, and W.

10 . The Fe-based electroplated steel sheet according to claim 8 , wherein the Fe-based electroplated steel sheet is resistance-welded with a hot-dip galvanized steel sheet.

11 . A hot-dip galvanized steel sheet comprising:
the Fe-based electroplated steel sheet according to claim 8 ; and a hot-dip galvanized layer disposed on the Fe-based electroplated layer included in the Fe-based electroplated steel sheet.

12 . The method for producing an Fe-based electroplated steel sheet according to claim 2 , wherein the transition metal ions contained in the Fe-based electroplating solution are ions of at least one transition metal selected from the group consisting of Ti, V, Cr, Mn, Ni, Cu, Nb, Mo, and W.

13 . The method for producing an Fe-based electroplated steel sheet according to claim 3 , wherein the transition metal ions contained in the Fe-based electroplating solution are ions of at least one transition metal selected from the group consisting of Ti, V, Cr, Mn, Ni, Cu, Nb, Mo, and W.

14 . The method for producing an Fe-based electroplated steel sheet according to claim 2 , wherein a coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 5.0 to 20.0 g/m 2 .

15 . The method for producing an Fe-based electroplated steel sheet according to claim 3 , wherein a coating amount of the Fe-based electroplated layer per one surface of the base steel sheet is 5.0 to 20.0 g/m 2 .

16 . A method for producing a hot-dip galvanized steel sheet, the method comprising subjecting an Fe-based electroplated steel sheet obtained by the method according to claim 2 to a hot-dip galvanizing treatment.

17 . A method for producing a hot-dip galvanized steel sheet, the method comprising subjecting an Fe-based electroplated steel sheet obtained by the method according to claim 3 to a hot-dip galvanizing treatment.

18 . The method for producing a hot-dip galvanized steel sheet according to claim 16 , further comprising subjecting the Fe-based electroplated steel sheet to an alloying treatment after the hot-dip galvanizing treatment.

19 . The method for producing a hot-dip galvanized steel sheet according to claim 17 , further comprising subjecting the Fe-based electroplated steel sheet to an alloying treatment after the hot-dip galvanizing treatment.

20 . A hot-dip galvanized steel sheet comprising:
the Fe-based electroplated steel sheet according to claim 9 ; and a hot-dip galvanized layer disposed on the Fe-based electroplated layer included in the Fe-based electroplated steel sheet.

Assignees

• Jfe Steel Corp

Inventors

• Makimizu Yoichi
• Yamamoto Shunsuke
• Okumura Yusuke
• Hoshino Katsuya
• Okumura Ei
• Takashima Katsutoshi

Classifications

• C25D3/562

  containing more than 50% by weight of iron or nickel or cobalt · CPC title

• C23C28/025

  with at least one zinc-based layer · CPC title

• C23C2/26

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

• C22C38/06

  containing aluminium · CPC title

• C22C38/02

  containing silicon · CPC title