Laser enhancements of cold sprayed deposits

Abstract

A process for depositing a powder metal onto a substrate is performed by providing a substrate, depositing at least one layer of powder metal onto a surface of the substrate using a non-oxidizing carrier gas so that the powder metal plastically deforms without melting and bonds to a surface upon impact with the surface, and subjecting the at least one powder metal deposited layer to a treatment to improve density and/or raise a temperature of the at least one powder metal deposited layer. In a preferred embodiment of the present invention, the treatment to improve density and/or raise a temperature of the at least one powder metal deposited layer is a laser treatment.

1 . A process for depositing a powder metal onto a substrate comprising the steps of: 
 providing a substrate;    depositing at least one layer of powder metal onto a surface of said substrate using a non-oxidizing carrier gas so that said powder metal plastically deforms without melting and bonds to a surface upon impact with said surface; and    subjecting said at least one powder metal deposited layer to a treatment to improve density and/or raise a temperature of said at least one powder metal deposited layer.    
   
   
       2 . The process according to  claim 1 , wherein said subjecting step comprises utilizing a laser to improve said density and/or raise said temperature.  
   
   
       3 . The process according to  claim 1 , wherein said depositing step comprises depositing multiple layers of said powder metal.  
   
   
       4 . The process according to  claim 3 , wherein said subjecting step is performed after each said layer is deposited.  
   
   
       5 . The process according to  claim 4 , wherein each said subjecting step comprises utilizing a laser to improve said density and/or raise said temperature.  
   
   
       6 . The process according to  claim 1 , wherein said depositing step comprises depositing multiple layers of said powder metal and said subjecting step is performed after said multiple layers have been deposited.  
   
   
       7 . The process according to  claim 1 , wherein said depositing step comprises providing said powder metal in particle form having a particle size in the range of from 5 microns to 50 microns and accelerating said particles to a speed in the range of from 825 m/s to 1400 m/s.  
   
   
       8 . The process according to  claim 7 , wherein said accelerating step comprises accelerating said particles to a speed in the range of from 850 m/s to 1200 m/s.  
   
   
       9 . The process according to  claim 7 , wherein said depositing step further comprises feeding said powder metal 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.  
   
   
       10 . The process according to  claim 9 , wherein said feeding step comprises feeding said metal powder to said spray nozzle at a feed rate of from 15 grams/min to 50 grams/min.  
   
   
       11 . The process according to  claim 9 , 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.  
   
   
       12 . The process according to  claim 11 , 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.  
   
   
       13 . The process according to  claim 9 , 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.  
   
   
       14 . The process according to  claim 13 , wherein said feeding step comprises feeding said nitrogen to said nozzle at a flow rate of from 4.0 SCFM to 10 SCFM.  
   
   
       15 . The process according to  claim 7 , wherein said depositing step comprises passing said metal powder 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.  
   
   
       16 . The process according to  claim 15 , wherein said passing step comprising passing said metal powder 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.  
   
   
       17 . The process according to  claim 15 , wherein said main gas temperature is in the range of from 725 degrees Fahrenheit to 900 degrees Fahrenheit at a spray pressure in the range of from 275 psi to 375 psi.  
   
   
       18 . The process according to  claim 15 , 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.  
   
   
       19 . The process according to  claim 18 , 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.  
   
   
       20 . The process according to  claim 15 , 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.  
   
   
       21 . The process according to  claim 20 , wherein said 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.  
   
   
       22 . The process according to  claim 1 , wherein said depositing step comprises depositing each layer at a thickness of from 0.002 inches to 0.020 inches.  
   
   
       23 . An apparatus for depositing a powder metal onto a substrate comprising: 
 means for depositing at least one layer of powder metal onto a surface of said substrate using a non-oxidizing carrier gas so that said powder metal plastically deforms without melting and bonds to a surface upon impact with said surface; and    means for subjecting said at least one powder metal deposited layer to a treatment to improve density and/or raise a temperature of said at least one powder metal deposited layer.    
   
   
       24 . An apparatus according to  claim 23 , wherein said subjecting means comprises a laser.  
   
   
       25 . An apparatus according to  claim 23 , wherein said depositing means comprises: 
 a source of powder metal; and    means for delivering said powder metal to a convergent-divergent spray nozzle so that said powder metal exits said nozzle at a speed of from 825 m/s to 1400 m/s.    
   
   
       26 . An apparatus according to  claim 25 , wherein said delivering means comprises means for supplying a carrier gas selected from the group consisting of helium, nitrogen, another inert gas, and mixtures thereof.  
   
   
       27 . An apparatus according to  claim 25 , wherein said subjecting means comprises a laser attached to said spray nozzle.