Steel sheet coated with a metallic coating based on aluminum

Patent metadata

Field	Value
Publication number	US-10889884-B2
Application number	US-201916359751-A
Country	US
Kind code	B2
Filing date	Mar 20, 2019
Priority date	Jul 30, 2015
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A steel sheet with a metallic coating is provided. A composition of the metallic coating includes from 2.0 to 24.0% by weight of zinc, from 7.1 to 12.0% by weight of silicon, optionally from 1.1 to 8.0% by weight of magnesium, and optionally additional elements chosen from Pb, Ni, Zr, or Hf. The content by weight of each additional element is less than 0.3%. A balance of the composition is aluminum, unavoidable impurities and residual elements. A ratio Al/Zn is from 4.0 to 6.0.

First claim

What is claimed is:

1. A steel sheet coated with a metallic coating, the metallic coating comprising:
10 to 20% by weight of zinc;
7.1 to 12.0% by weight of silicon;
1.1 to 8.0% by weight of magnesium;
optionally additional elements chosen from Pb, Ni, Zr, or Hf, a content by weight of each additional element of the additional elements if present being less than 0.3% by weight; and
a balance being aluminum and unavoidable impurities and residuals elements, a weight ratio of Al/Zn being from 4.0 to 6.0; the coating not including Sn and not including In;
wherein a microstructure of the coating includes an Al—Zn phase, a Mg 2 Si phase, and a MgZn 2 phase and wherein a thickness of the coating is between 10 and 35 μm.

2. The steel sheet according to claim 1 , wherein the coating comprises from 10.0 to 15.0% by weight of zinc.

3. The steel sheet according to claim 1 , wherein the coating comprises from 8.1 to 10.0% by weight of silicon.

4. The steel sheet according to claim 1 , wherein the coating comprises from 3.0 to 8.0% by weight of magnesium.

5. The steel sheet according to claim 4 , wherein the coating comprises from 3.0 to 5.0% by weight of magnesium.

6. The steel sheet according to claim 1 , wherein an amount of the aluminum is greater than 71% by weight.

7. The steel sheet according to claim 1 , wherein an amount of the aluminum is greater than 76% by weight.

8. The steel sheet according to claim 1 , wherein the thickness of the coating is between 12 and 18 μm.

9. The steel sheet according to claim 1 , wherein the thickness of the coating is between 26 and 31 μm.

10. The steel sheet according to claim 1 , wherein the coating further does not include any elements selected from Cr, Mn, Ti, Ce, La, Nd, Pr, Ca, Bi, and Sb or their combinations.

11. The steel sheet according to claim 1 , wherein the steel sheet is 22MnB5 steel.

Assignees

• Arcelormittal

Inventors

• Allely Christian
• Machado Amorim Tiago
• De Strycker Joost
• Van Den Bergh Krista Godelieve Oscar

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

• C22C38/58

  with more than 1.5% by weight of manganese · CPC title

• C22C38/54

  with boron · CPC title

• C22C38/50

  with titanium or zirconium · CPC title

• C22C38/48

  with niobium or tantalum · CPC title