Cold gas dynamic spraying of high strength copper

Abstract

A process for forming an article, such as a combustion chamber liner, comprises the steps of providing a mandrel formed from a material, such as an aluminum containing material, having a net shape of the article to be made, depositing a powdered metal material onto the mandrel without melting the powdered metal material, and removing the material forming the mandrel to leave a free standing monolithic article. In a preferred embodiment of the present invention, the powdered metal material comprises powdered GRCop-84. Alternatively, the powdered metal material may be GRCop-42.

1 - 27 . (canceled) 
   
   
       28 . A combustion chamber liner comprising a body formed from a copper base alloy containing chromium and niobium and having a microstructure with a uniform distribution of dispersoids of Cr 2 Nb particles in a copper matrix with fine Cr 2 Nb particles being located at copper grain boundaries. 
   
   
       29 . A combustion chamber according to  claim 28 , wherein said dispersoids comprise about 14 vol % of the alloy with the remainder being pure copper. 
   
   
       30 . A combustion chamber liner according to  claim 28 , wherein said copper base alloy contains from 2.0 to 10.0 wt % chromium and 1.0 to 10.0 wt % niobium. 
   
   
       31 . A combustion chamber liner according to  claim 28 , having at least one coolant passageway having at least one internal feature for increasing heat transfer by disrupting the flow through said at least one internal passageway. 
   
   
       32 . A combustion chamber liner according to  claim 31 , wherein said at least one internal feature comprises at least one of a bump, a chevron, and a flow trip. 
   
   
       33 . A system for manufacturing an article comprising:
 a mandrel formed from a material having a net shape of the article to be made; and   means for depositing at least one layer of a powdered copper alloy containing chromium and niobium onto said mandrel without melting said powdered copper alloy and thereby creating a deposited article having the shape of a combustion chamber liner on said mandrel and having a uniform distribution of Cr 2 Nb particles in a copper matrix with fine Cr 2 Nb particles being located at copper grain boundaries.   
   
   
       34 . A system according to  claim 33 , further comprising means for removing said material forming said mandrel so as to leave said combustion chamber liner as a free standing combustion chamber liner. 
   
   
       35 . A system according to  claim 33 , wherein said mandrel is formed from an aluminum containing material. 
   
   
       36 . A system according to  claim 33 , wherein said depositing means comprises means for accelerating particles of said powdered copper alloy to a velocity so that upon impact the particles plastically deform and bond to a surface of said mandrel. 
   
   
       37 . A system according to  claim 33 , wherein said depositing means comprises a spray gun having a nozzle, means for supplying said powdered copper alloy in particle form to said nozzle, said supplying means including a carrier gas for feeding said powdered copper alloy to said nozzle, and a main gas for depositing the particles onto the mandrel. 
   
   
       38 . A system according to  claim 37 , wherein said carrier gas is selected from the group consisting of hydrogen, nitrogen, and mixtures thereof. 
   
   
       39 . A system according to  claim 37 , wherein said main gas is selected from the group consisting of hydrogen, nitrogen, and mixtures thereof.