Cold spray nozzle

Patent metadata

Field	Value
Publication number	US-10597784-B2
Application number	US-201715652782-A
Country	US
Kind code	B2
Filing date	Jul 18, 2017
Priority date	Jul 18, 2017
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

A spray nozzle has a body having a flow passage. At least along a portion of the flow passage the body has a depth-wise compositional variation having: a cemented carbide first region; and a cemented carbide second region closer to the flow passage than the first region and having a higher boron content than a boron content, if any, of the first region.

First claim

What is claimed is:

1. A spray nozzle comprising:
a body having a flow passage, wherein at least along a portion of the flow passage the body has a depth-wise compositional variation comprising:
a cemented carbide first region; and
a cemented carbide second region closer to the flow passage than the first region and having a higher boron content than a boron content, if any, of the first region.

2. The spray nozzle of claim 1 wherein:
the flow passage is converging-diverging.

3. The spray nozzle of claim 1 wherein the first region has a weight percent composition of:
at least 80 percent tungsten carbide;
at least 5.0 percent cobalt;
no more than 0.1 percent boron, if any; and
other elements, if any, no more than 1.0 percent total and no more than 0.75 percent individually.

4. The spray nozzle of claim 1 wherein the second region has a boron content of at least 0.2 weight percent higher than a boron content of the first region, if any.

5. The spray nozzle of claim 1 wherein the second region has a boron content of at least 1.0 weight percent higher than a boron content of the first region, if any.

6. The spray nozzle of claim 1 wherein the second region has a boron content of at least 0.2 weight percent.

7. The spray nozzle of claim 1 wherein:
a boron content at a depth in the second region is 1.0 weight percent to 10.0% weight percent.

8. A cold spray apparatus including the spray nozzle of claim 1 and further comprising:
a powder source; and
a carrier gas source.

9. The cold spray apparatus of claim 8 further comprising:
a heater for heating the carrier gas.

10. A method for manufacturing the spray nozzle of claim 1 , the method comprising:
placing a boriding powder into a passageway of a cemented carbide precursor of the spray nozzle; and
heating the precursor so as to diffuse boron from the boriding powder into the precursor.

11. The method of claim 10 wherein:
the cemented carbide precursor has at least 70% WC by weight.

12. The method of claim 11 wherein:
the cemented carbide precursor has at least 4.0% combined Ni and Co by weight.

13. The method of claim 11 wherein the cemented carbide precursor has one or more:
at least 6.0% combined Ni and Co by weight;
up to 5.0% TaC, if any, by weight;
up to 5.0% total other, if any by weight; and
up to 2.0% individually other, if any, by weight.

14. The method of claim 10 further comprising:
forming the precursor by machining the passageway.

15. The method of claim 10 wherein:
the boriding powder comprises least 10 wt % B and 5.0 wt % KBF 4 .

16. The method of claim 10 wherein:
the heating is to at least 850° C.

17. The method of claim 10 wherein:
the heating is to 850° C. to 1000° C.

18. A method for using the spray nozzle of claim 1 , the method comprising:
flowing a powder and a carrier gas through the nozzle; and
directing a spray of the powder from the nozzle to a substrate.

19. The method of claim 18 further comprising:
heating the carrier gas.

20. The method of claim 18 wherein the powder comprises at least one of:
ceramic particles; and
metallic particles.

Assignees

• United Technologies Corp

Inventors

• Mcgee Randolph C
• Nardi Aaron T

Classifications

• B05B15/18

  for improving resistance to wear, e.g. inserts or coatings; for indicating wear; for handling or replacing worn parts · CPC title

• C23C24/04 Primary

  Impact or kinetic deposition of particles · CPC title

• B05B7/205 Primary

  the material to be sprayed being originally a particulate material · CPC title