Method of making metallic composite foam components

Abstract

A method of producing a metallic composite component or a blade for a gas turbine engine includes: providing a core of a ceramic or metallic foam material; disposing the core in a mold having a cavity defining the exterior contour of the component or blade includes; injecting the mixture into the mold so as to penetrate the intracellular volume of the foam; removing a majority of the binder from the preform; and heating the preform to remove the remainder of the binder and sinter the metal powder together to form the finished component or blade. A preform for a metallic composite component includes a core of a foam material having ceramic or metallic cell walls with intracellular volume therebetween. The core defines at least a portion of the exterior contour of the component. A mixture of a metallic powder and a binder is disposed in the intracellular volume.

1 . A method of producing a metallic composite component, comprising:
 providing a core comprising a foam material having ceramic or metallic cell walls with intracellular volume therebetween;   disposing the core in a mold having a cavity defining the exterior contours of the component;   providing a mixture of a metallic powder and a binder;   melting the binder and injecting the mixture into the mold so as to penetrate the intracellular volume;   removing a portion of the binder from the preform; and   heating the preform to remove the remainder of the binder and to sinter the metal powder together to form the finished component.   
   
   
       2 . The method of  claim 1  further comprising performing a hot isostatic pressing treatment on the component after the heating step. 
   
   
       3 . The method of  claim 1  wherein the core defines at least a portion of the exterior contours of the component. 
   
   
       4 . The method of  claim 1  wherein the core is smaller than the component and defines an internal reinforcement member. 
   
   
       5 . The method of  claim 1  wherein the majority of the binder is removed by washing the preform with a solvent selected to dissolve the binder but not the metallic powder. 
   
   
       7 . The method of  claim 1  wherein the preform is disposed in a chamber provided with a controlled composition atmosphere during the step of heating. 
   
   
       8 . The method of  claim 7  wherein the atmosphere is an inert gas. 
   
   
       9 . The method of  claim 7  wherein the atmosphere is a reducing atmosphere. 
   
   
       10 . The method of  claim 1  wherein the preform is maintained under a vacuum during the heating. 
   
   
       11 . The method of  claim 1  wherein the metallic powder is selected from the group comprising iron, nickel, cobalt, titanium, and alloys thereof. 
   
   
       12 . The method of  claim 1  wherein the cell walls are ceramic. 
   
   
       13 . The method of  claim 12  wherein the cell walls consist essentially of alumina. 
   
   
       14 . The method of  claim 1  wherein the component is an airfoil for a gas turbine engine. 
   
   
       15 . A method of producing a blade for a gas turbine engine having an airfoil with a leading edge, a trailing edge, a tip, a root, and opposed sides and, the method comprising:
 providing a core comprising a foam material having ceramic or metallic cell walls with intracellular volume therebetween;   disposing the core in a mold having a cavity defining the exterior contour of the airfoil;   providing a mixture of a metallic powder and a binder;   melting the binder and injecting the mixture into the mold so as to penetrate the intracellular volume;   removing a portion of the binder from the preform; and   heating the preform to remove the remainder of the binder and to sinter the metal powder together to form the finished blade.   
   
   
       16 . The method of  claim 15  further comprising performing a hot isostatic pressing treatment on the blade after the heating step. 
   
   
       17 . The method of  claim 15  wherein the core defines at least a portion of the exterior contours of the airfoil. 
   
   
       18 . The method of  claim 15  wherein the core is smaller than the airfoil and defines an internal reinforcement member. 
   
   
       19 . The method of  claim 15  wherein the cell walls are ceramic. 
   
   
       20 . The method of  claim 15  wherein the metallic powder is selected from the group comprising iron, nickel, cobalt, and alloys thereof. 
   
   
       21 . A preform for a metallic composite component, comprising:
 a core comprising a foam material having ceramic or metallic cell walls with intracellular volume therebetween; the core defining at least a portion of the exterior contour of the component; and   a mixture of a metallic powder and a binder disposed in the intracellular volume.   
   
   
       22 . The preform of  claim 1  wherein the core is smaller than the component and defines an internal reinforcement member. 
   
   
       23 . The preform of  claim 21  wherein the cell walls consist essentially of alumina. 
   
   
       24 . The preform of  claim 21  wherein the component is an airfoil for a gas turbine engine. 
   
   
       25 . The method of  claim 21  wherein the metallic powder is selected from the group comprising iron, nickel, cobalt, and alloys thereof.