Painted steel sheet provided with a zinc coating

Patent metadata

Field	Value
Publication number	US-11525182-B2
Application number	US-201916381488-A
Country	US
Kind code	B2
Filing date	Apr 11, 2019
Priority date	Aug 1, 2013
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A steel sheet is provided with a coating having at least one layer of zinc and a top layer of paint applied by cataphoresis. The zinc layer is deposited by a jet vapor deposition process in a deposition chamber maintained at a pressure between 6·10−2 mbar and 2·10−1 mbar. A fabrication method and an installation are also provided.

First claim

What is claimed is:

1. A method for the fabrication of a coated and painted sheet comprising the steps of:
providing a deposition chamber;
providing an ejection chamber inside the deposition chamber;
providing an evaporation crucible, the evaporation crucible having liquid zinc, said liquid zinc consisting of pure zinc and unavoidable impurities acquired during production and present in trace quantities;
heating the liquid zinc to form a vapor, and passing the vapor to the ejection chamber via a conduit;
passing a steel sheet through the deposition chamber and during said passing:
maintaining a pressure P chamber inside a deposition chamber between 6·10 −2 mbar and 2·10 −1 mbar;
maintaining the ejection chamber at a pressure P eject , a ratio of the pressure P chamber to P eject being between 2·10 −3 and 5.5·10 −2 , and
coating the steel sheet with a sonic vapor jet of zinc inside the deposition chamber; and

painting said coated steel sheet.

2. The method according to claim 1 , wherein a distance d between an upper portion of a slot of the ejection chamber and the steel sheet to be coated is between 20 and 60 mm.

3. The method according to claim 1 , wherein said painting includes applying a top layer of paint over the zinc coating by cataphoresis.

4. The method according to claim 1 , wherein said painting includes applying a cataphoresis layer.

5. The method according to claim 4 , wherein said painting includes applying a phosphate layer prior to application of the cataphoresis layer.

6. The method according to claim 4 , wherein said applying the cataphoresis layer comprises quenching the sheet in a cataphoresis bath.

7. The method according to claim 6 , wherein prior to said quenching, the sheet is subjected to a phosphate treatment.

8. The method according to claim 1 , wherein said painting includes applying a layer of primer paint to the sheet.

9. The method according to claim 7 , wherein after said quenching, a layer of primer paint is applied to the sheet.

10. The method according to claim 8 , wherein a layer of base paint is applied over the primer paint.

11. The method according to claim 10 , wherein a layer of varnish is applied over the base paint.

12. The method according to claim 7 , wherein the phosphate treatment applies a phosphate layer having a weight between 1.5 and 5 g/m 2 .

13. The method according to claim 6 , wherein said cataphoresis bath provides a cataphoresis layer with a thickness of 15 to 25 μm.

14. The method according to claim 4 , wherein the steel sheet has no more than 2.7 crater-type defects per square decimeter on a surface of the cataphoresis layer.

15. The method according to claim 4 , wherein the top layer of paint is applied directly over the zinc coating by cataphoresis.

Assignees

• Arcelormittal

Inventors

• Chaleix Daniel
• Jacques Daniel
• Pace Sergio
• Silberberg Eric
• Schmitz Bruno
• Vanden Eynde Xavier

Classifications

• C25D13/16

  Wires; Strips; Foils · CPC title

• C23C14/584

  Non-reactive treatment · CPC title

• C25D13/02

  with inorganic material · CPC title

• C23C28/34

  including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates · CPC title

• C23C14/16 Primary

  on metallic substrates or on substrates of boron or silicon · CPC title