Metal material hydrophobic surface treatment methods

Patent metadata

Field	Value
Publication number	US-11345987-B2
Application number	US-201816229199-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Dec 21, 2018
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

A method for treating a metal material to make a surface portion hydrophobic. The method includes oxidizing an untreated surface portion of the metal material to form an oxidized surface portion. The untreated surface portion has metal atoms. The oxidizing step forming bonds between the metal atoms and oxygen atoms. The method further includes doping the oxidized surface portion with a liquid containing a fluorine-containing salt to form a fluorinated surface portion. The doping step forming bonds between fluorine atoms and at least a portion of the metal atoms and the oxygen atoms. The fluorinated surface portion is hydrophobic.

First claim

What is claimed is:

1. A method for treating a metal material comprising:
oxidizing an untreated surface portion of the metal material to form an oxidized surface portion, the untreated surface portion having metal atoms, and the oxidizing step forming bonds between the metal atoms and oxygen atoms; and
doping the oxidized surface portion with a liquid containing a fluorine-containing salt to form a fluorinated surface portion, the doping step forming bonds between fluorine atoms and at least a portion of the metal atoms and the oxygen atoms, and the fluorinated surface portion being hydrophobic.

2. The method of claim 1 , wherein the metal material is a stainless steel alloy.

3. The method of claim 1 , wherein the untreated surface portion has a thickness of 20 nm to 20 μm.

4. The method of claim 1 , wherein the liquid is an organic solvent.

5. The method of claim 1 , wherein the oxidizing step includes heating the untreated surface portion at an elevated temperature for a period of time.

6. The method of claim 5 , wherein the elevated temperature is 700 to 1,000° C. and the period of time is 1 to 2 hours.

7. The method of claim 1 , wherein the oxidizing step includes immersing the metal material in an aqueous bath of an acid at a temperature for a period of time.

8. The method of claim 7 , wherein the acid is nitric or sulfuric acid.

9. The method of claim 7 , wherein the temperature is 0 to 120° C. and the period of time is 2 to 10 hours.

10. The method of claim 1 , wherein the oxidizing step includes oxygen plasma treating the untreated surface portion to form the oxidized surface portion.

11. The method of claim 1 , wherein the fluorine-containing salt is lithium tetrafluoroborate (LiBF 4 ), lithium hexafluorophosphate (LiBF 6 ), sodium tetrafluoroborate (NaBF 4 ), or a combination thereof.

12. A method for treating a metal material comprising:
selecting a depth of an untreated surface portion of the metal material based on a threshold concentration of a metal material combination including chromium atoms and nickel atoms in the untreated surface portion;
oxidizing the untreated surface portion to form an oxidized surface portion by forming bonds between at least a portion of the chromium atoms and the nickel atoms in the metal material combination and oxygen atoms; and
doping the oxidized surface portion with a liquid containing a fluorine-containing salt to form a fluorinated surface portion, the doping step forming bonds between fluorine atoms and at least a portion of the chromium atoms and the nickel atoms in the metal material combination and the oxygen atoms, and the fluorinated surface portion being hydrophobic.

13. The method of claim 12 , wherein a contact angle of the fluorinated surface portion is greater than or equal to 90°.

14. The method of claim 12 , wherein a contact angle of the oxidized surface portion is less than 90°.

15. The method of claim 12 , wherein the metal material includes a bulk region, and a concentration of the chromium atoms and/or the nickel atoms are higher in the untreated surface region than the bulk region.

16. The method of claim 12 , wherein the liquid includes an organic solvent.

17. The method of claim 12 , wherein the fluorine-containing salt is LiBF 4 .

18. A method for treating a metal material comprising:
selecting a depth of an untreated surface portion of the metal material based on a threshold concentration of a metal material combination including chromium atoms and nickel atoms in the untreated surface portion, the metal material combination further includes molybdenum and/or manganese;
oxidizing the untreated surface portion to form an oxidized surface portion by forming bonds between at least a portion of the chromium atoms and the nickel atoms in the metal material combination and oxygen atoms; and
doping the oxidized surface portion with a liquid containing a fluorine-containing salt to form a fluorinated surface portion, the doping step forming bonds between fluorine atoms and at least a portion of the chromium atoms and the nickel atoms in the metal material combination and the oxygen atoms, and the fluorinated surface portion being hydrophobic.

19. The method of claim 18 , wherein the liquid includes an organic solvent.

20. The method of claim 18 , wherein the fluorine-containing salt is LiBF 4 .

Assignees

• Bosch Gmbh Robert

Inventors

• Cheng Lei
• Kim Soo
• Kornbluth Mordechai
• Mailoa Jonathan
• Samsonidze Georgy
• Craig Nathan
• Johnston Christina

Classifications

• C23C8/36

  using ionised gases, e.g. ionitriding · CPC title

• C21D6/005

  containing Mn · CPC title

• C23C8/60

  using solids, e.g. powders, pastes (using liquid suspensions of solids C23C8/40) · CPC title

• C23C8/02

  Pretreatment of the material to be coated (C23C8/04 takes precedence) · CPC title

• C23C22/02

  using non-aqueous solutions · CPC title