Applying bond coat to engine components using cold spray

Abstract

A process for applying a coating to a component used in an engine is provided. The process includes the steps of providing a component with at least one surface to be coated, and depositing at least one layer of powder coating material onto the at least one surface using a non-oxidizing carrier gas so that the powder coating material plastically deforms without melting and bonds to the at least one surface upon impact with the at least one surface. The process of the present invention has particular utility in applying bond coats to airfoil portions of turbine blades or vanes and to applying bond coats to combustion chamber liners.

1 - 2 . (canceled)  
   
   
       3 . The process according to  claim 24 , wherein said depositing step comprises providing said powder coating material in particle form having a particle size no greater than 10 microns.  
   
   
       4 . The process according to  claim 3 , wherein said depositing step comprises providing said powder coating material in particle form having a particle size in the range of from 5.0 microns to 10 microns.  
   
   
       5 . The process according to  claim 3 , wherein said depositing step comprises accelerating said particles to a speed in the range of from 825 m/s to 1400 m/s.  
   
   
       6 . The process according to  claim 5 , wherein said accelerating step comprises accelerating said particles to a speed in the range of from 850 m/s to 1200 m/s.  
   
   
       7 . The process according to  claim 5 , wherein said depositing step further comprises feeding said powdered coating material to a spray nozzle at a feed rate of from 10 grams/min to 100 grams/min using a carrier gas selected from the group consisting of helium, nitrogen, another inert gas, and mixtures thereof.  
   
   
       8 . The process according to  claim 7 , wherein said feeding step comprises feeding said metal powder to said spray nozzle at a feed rate of from 10 grams/min to 50 grams/min.  
   
   
       9 . The process according to  claim 7 , wherein said carrier gas is helium and said feeding step comprises feeding helium to said nozzle at a flow rate of from 0.001 SCFM to 50 SCFM.  
   
   
       10 . The process according to  claim 9 , wherein said feeding step comprises feeding said helium to said nozzle at a flow rate in the range of from 8.0 SCFM to 15 SCFM.  
   
   
       11 . The process according to  claim 7 , wherein said carrier gas comprises nitrogen and said feeding step comprises feeding said nitrogen to said nozzle at a flow rate of from 0.001 SCFM to 30 SCFM.  
   
   
       12 . The process according to  claim 11 , wherein said feeding step comprises feeding said nitrogen to said nozzle at a flow rate of from 4.0 SCFM to 10 SCFM.  
   
   
       13 . The process according to  claim 7 , wherein said depositing step comprises passing said powdered coating particles through said nozzle using a main gas selected from the group consisting of helium, nitrogen, another inert gas, and mixtures thereof at a main gas temperature in the range of from 600 degrees Fahrenheit to 1200 degrees Fahrenheit and at a spray pressure in the range of from 200 psi to 500 psi.  
   
   
       14 . The process according to  claim 13 , wherein said passing step comprising passing said powdered coating particles through said nozzle at a main gas temperature in the range of from 700 degrees Fahrenheit to 1000 degrees Fahrenheit at a spray pressure in the range of from 200 psi to 400 psi.  
   
   
       15 . The process according to  claim 13 , wherein said main gas temperature is in the range of from 725 degrees Fahrenheit to 900 degrees Fahrenheit at a spray temperature in the range of from 275 psi to 375 psi.  
   
   
       16 . The process according to  claim 13 , wherein said main gas comprises helium and said passing step comprises feeding said helium to said nozzle at a flow rate in the range of from 0.001 SCFM to 50 SCFM.  
   
   
       17 . The process according to  claim 16 , wherein said helium feeding step comprises feeding said helium to said nozzle at a flow rate in the range of from 15 SCFM to 35 SCFM.  
   
   
       18 . The process according to  claim 13 , wherein said main gas comprises nitrogen and said passing step comprises feeding said nitrogen to said nozzle at a feed rate in the range of from 0.001 SCFM to 30 SCFM.  
   
   
       19 . The process according to  claim 18 , wherein aid nitrogen feeding step comprises feeding said nitrogen to said nozzle at a feed rate in the range of from 4.0 to 8.0 SCFM.  
   
   
       20 . (canceled)  
   
   
       21 . The process according to  claim 24 , wherein said depositing step comprises forming a bond coat having a bond strength in the range up to 10 ksi or greater.  
   
   
       22 . The process according to  claim 24 , wherein said depositing step comprises depositing a MCrAlY material on said component where M is at least one of nickel and cobalt.  
   
   
       23 . The process according to  claim 24 , wherein said depositing step comprises depositing a coating which is at least 97% dense on said component.  
   
   
       24 . A process for applying a coating to a component comprising the steps of: 
 providing a component having at least one surface to be coated;    said component providing step comprises providing a combustion chamber liner formed from a nickel-based alloy or a copper based alloy;    depositing at least one layer of a powder coating material onto said at least one surface using a non-oxidizing carrier gas so that said powder coating material plastically deforms without melting and bonds to said at least one surface upon impact with said at least one surface; and    said depositing step comprises depositing said at least one layer on at least one surface of said combustion chamber liner.    
   
   
       25 . A process for applying a coating to a component comprising the steps of: 
 providing a component having at least one surface to be coated;    said component providing step comprises providing an engine component having an airfoil surface and a plurality of cooling holes in a said surface;    depositing at least one layer of a powder coating material onto said at least one surface using a non-oxidizing carrier gas so that said powder coating material plastically deforms without melting and bonds to said at least one surface upon impact with said at least one surface;    said depositing step comprises depositing said at least one layer of powder coating material without bridging said cooling holes in said surface; and    said depositing step further comprising feeding said powdered coating material to a spray nozzle at a feed rate of from 10 grams/min to 100 grams/min.    
   
   
       26 . The process according to  claim 24 , wherein said depositing step comprises depositing a copper based alloy material.  
   
   
       27 . The process according to  claim 24 , wherein said depositing step comprises depositing a copper chromium alloy material.  
   
   
       28 . The process according to  claim 24 , wherein said depositing step comprises depositing a copper-chromium-aluminum alloy material.  
   
   
       29 . The process according to  claim 25 , wherein said depositing step comprises providing said powder coating material in particle form having a particle size no greater than 10 microns.  
   
   
       30 . The process according to  claim 29 , wherein said depositing step comprises providing said powder coating material in particle form having a particle size in the range of from 5.0 microns to 10 microns.  
   
   
       31 . The process according to  claim 29 , wherein said depositing step comprises accelerating said particles to a speed in the range of from 825 m/s to 1400 m/s.  
   
   
       32 . The process according to  claim 31 , wherein said accelerating step comprises accelerating said particles to a speed in the range of from 850 m/s to 1200 m/s.  
   
   
       33 . The process according to  claim 31 , wherein said depositing step further comprising using a carrier gas selected from the group consisting of helium, nitrogen, another inert gas, and mixtures thereof to feed said powder material to said nozzle.  
   
   
       34 . The process according to  claim 33 , wherein said feeding step comprises feeding said metal powder to said spray nozzle at a feed rate of from 10 grams/min to 50 grams/min.  
   
   
       35 . The process according to  claim 33 , wherein said carrier gas is helium and said feeding step comprises feeding helium to said nozzle at a flow rate of from 0.001 SCFM to 50 SCFM.  
   
   
       36 . The process according to  claim 35 , wherein said feeding step comprises feeding said helium to said nozzle at a flow rate in the range of from 8.0 SCFM to 15 SCFM.  
   
   
       37 . The process according to  claim 33 , wherein said carrier gas comprises nitrogen and said feeding step comprises feeding said nitrogen to said nozzle at a flow rate of from 0.001 SCFM to 30 SCFM.  
   
   
       38 . The process according to  claim 37 , wherein said feeding step comprises feeding said nitrogen to said nozzle at a flow rate of from 4.0 SCFM to 10 SCFM.  
   
   
       39 . The process according to  claim 33 , wherein said depositing step comprises passing said powdered coating particles through said nozzle using a main gas selected from the group consisting of helium, nitrogen, another inert gas, and mixtures thereof at a main gas temperature in the range of from 600 degrees Fahrenheit to 1200 degrees Fahrenheit and at a spray pressure in the range of from 200 psi to 500 psi.  
   
   
       40 . The process according to  claim 39 , wherein said passing step comprising passing said powdered coating particles through said nozzle at a main gas temperature in the range of from 700 degrees Fahrenheit to 1000 degrees Fahrenheit at a spray pressure in the range of from 200 psi to 400 psi.  
   
   
       41 . The process according to  claim 39 , wherein said main gas temperature is in the range of from 725 degrees Fahrenheit to 900 degrees Fahrenheit at a spray temperature in the range of from 275 psi to 375 psi.  
   
   
       42 . The process according to  claim 39 , wherein said main gas comprises helium and said passing step comprises feeding said helium to said nozzle at a flow rate in the range of from 0.001 SCFM to 50 SCFM.  
   
   
       43 . The process according to  claim 42 , wherein said helium feeding step comprises feeding said helium to said nozzle at a flow rate in the range of from 15 SCFM to 35 SCFM.  
   
   
       44 . The process according to  claim 39 , wherein said main gas comprises nitrogen and said passing step comprises feeding said nitrogen to said nozzle at a feed rate in the range of from 0.001 SCFM to 30 SCFM.  
   
   
       45 . The process according to  claim 44 , wherein aid nitrogen feeding step comprises feeding said nitrogen to said nozzle at a feed rate in the range of from 4.0 to 8.0 SCFM.  
   
   
       46 . The process according to  claim 25 , wherein said depositing step comprises forming a bond coat having a bond strength in the range up to 10 ksi or greater.  
   
   
       47 . The process according to  claim 25 , wherein said depositing step comprises depositing a MCrAlY material on said component where M is at least one of nickel and cobalt.  
   
   
       48 . The process according to  claim 25 , wherein said depositing step comprises depositing a coating which is at least 97% dense on said component.