Depositing a structurally hard, wear resistant metal coating onto a substrate

Patent metadata

Field	Value
Publication number	US-10787743-B2
Application number	US-201715688337-A
Country	US
Kind code	B2
Filing date	Aug 28, 2017
Priority date	Aug 28, 2017
Publication date	Sep 29, 2020
Grant date	Sep 29, 2020

Abstract

An example method of coating a substrate involves cleaning the substrate and, after cleaning the substrate, sensitizing the substrate using a sensitizing solution including tin chloride and hydrochloric acid. The method also involves, after sensitizing the substrate, activating the substrate in an activating solution including palladium chloride and hydrochloric acid. Further, the method involves subsequently neutralizing the substrate using a neutralizing solution including ammonium hydroxide. Still further, the method involves, after neutralizing the substrate, depositing an electroless nickel layer on the substrate. The method may then involve depositing an electrolytic nickel layer on top of the electroless nickel layer, and depositing an outer layer of metallic material, ceramic material, polymeric material, or any combination thereof on top of the electrolytic nickel layer.

First claim

What is claimed is:

1. A method of coating a substrate, the method comprising:
cleaning the substrate, wherein cleaning the substrate comprises:
sanding the substrate to form a sanded substrate,
immersing the sanded substrate in a first acidic solution comprising acetone, hydroquinone, and catechol,
rinsing the sanded substrate in water to form a rinsed substrate, and
immersing the rinsed substrate in a second acidic solution comprising phosphoric

acid and potassium dichromate in order to clean the substrate;
after cleaning the substrate, sensitizing the substrate using a sensitizing solution comprising tin chloride and hydrochloric acid;
after sensitizing the substrate, activating the substrate in an activating solution comprising palladium chloride and hydrochloric acid;
subsequently neutralizing the substrate using a neutralizing solution comprising ammonium hydroxide; and
after neutralizing the substrate, depositing an electroless nickel layer on the substrate.

2. The method of claim 1 , wherein the substrate is non-conductive.

3. The method of claim 2 , wherein the substrate comprises a fiber-reinforced plastic.

4. The method of claim 2 , wherein the substrate comprises an engineering plastic.

5. The method of claim 1 , wherein the sensitizing solution comprises between 5 g/l to 15 g/l of tin chloride and between 20 ml/l to 60 ml/l of hydrochloric acid.

6. The method of claim 1 , wherein the activating solution comprises between 0.25 g/l to 1.5 g/l of palladium chloride and between 5 ml/l to 15 ml/l of hydrochloric acid.

7. The method of claim 1 , further comprising depositing an outer layer of metallic material, ceramic material, polymeric material, or any combination thereof on the electroless nickel layer.

8. The method of claim 7 , wherein the outer metallic material comprises a nickel-cobalt-phosphorous alloy.

9. The method of claim 7 , wherein the outer metallic material comprises a cobalt-phosphorous alloy.

10. The method of claim 7 , wherein the outer metallic material comprises chromium.

11. The method of claim 1 , further comprising heating the second acidic solution prior to immersing the substrate in the second acidic solution.

12. The method of claim 1 , further comprising heating the activating solution prior to activating the substrate.

13. The method of claim 1 , wherein depositing the electroless nickel layer comprises immersing the substrate in a nickel bath.

14. A method of coating a substrate, the method comprising:
cleaning the substrate;
after cleaning the substrate, sensitizing the substrate using a sensitizing solution comprising tin chloride and hydrochloric acid;
after sensitizing the substrate, activating the substrate in an activating solution comprising palladium chloride and hydrochloric acid;
subsequently neutralizing the substrate using a neutralizing solution comprising ammonium hydroxide;
after neutralizing the substrate, depositing an electroless nickel layer on the substrate; and
depositing an outer layer on the electroless nickel layer, wherein the outer layer comprises an iron-phosphorous alloy.

15. A method of coating a substrate, the method comprising:
cleaning the substrate, wherein cleaning the substrate comprises:
sanding the substrate to form a sanded substrate,
immersing the sanded substrate in a first acidic solution comprising acetone, hydroquinone, and catechol,
rinsing the sanded substrate in water to form a rinsed substrate, and
immersing the rinsed substrate in a second acidic solution comprising phosphoric

acid and potassium dichromate in order to clean the substrate;
after cleaning the substrate, sensitizing the substrate using a sensitizing solution comprising tin chloride and hydrochloric acid;
after sensitizing the substrate, activating the substrate in an activating solution comprising palladium chloride and hydrochloric acid;
subsequently neutralizing the substrate using a neutralizing solution comprising ammonium hydroxide;
after neutralizing the substrate, depositing an electroless nickel layer on the substrate;
depositing, using an electric current, an electrolytic nickel layer on top of the electroless nickel layer; and
depositing an outer layer of metallic material, ceramic material, polymeric material, or any combination thereof on top of the electrolytic nickel layer.

16. The method of claim 15 , wherein the substrate is non-conductive.

17. The method of claim 16 , wherein the substrate comprises a fiber-reinforced plastic.

18. The method of claim 16 , wherein the substrate comprises an engineering plastic.

19. The method of claim 15 , wherein the sensitizing solution comprises between 5 g/l to 15 g/l of tin chloride and between 20 ml/l to 60 ml/l of hydrochloric acid.

20. The method of claim 15 , wherein the activating solution comprises between 0.25 g/l to 1.5 g/l of palladium chloride and between 5 ml/l to 30 ml/l of hydrochloric acid.

Assignees

• Boeing Co

Inventors

• Paesano Antonio

Classifications

• C25D5/54

  Electroplating of non-metallic surfaces (C25D7/12 takes precedence) · CPC title

• C23C18/165 Primary

  Multilayered product (layered product B32B) · CPC title

• C23C18/1653

  Two or more layers with at least one layer obtained by electroless plating and one layer obtained by electroplating · CPC title

• C23C18/32

  Coating with nickel, cobalt or mixtures thereof with phosphorus or boron (C23C18/50 takes precedence) · CPC title

• C23C18/208

  with use of metal first · CPC title