Method for attaching a porous metal layer to a metal substrate

Abstract

A method for attaching a porous metal layer to a dense metal substrate, wherein the method is particularly useful in forming orthopedic implants such as femoral knee components or acetabular cups. The method, in one embodiment thereof, comprises providing a structured porous layer; providing a dense metal substrate; providing a binding mixture; applying the binding mixture to the exterior of the substrate; placing the porous layer against the substrate such that the binding mixture is disposed there between forming an assembly; and heat treating the assembly to metallurgically bond the porous layer to the substrate.

1 . A method for attaching a porous metal structure to a metal substrate, the method comprising: 
 providing a metal substrate;    providing the porous metal structure;    contouring a surface of the porous metal structure;    placing the porous structure against the substrate such that the contoured surface of the porous structure is in contact with the substrate, thereby forming an assembly; and    heating the assembly to metallugically bond the porous structure and the substrate.    
   
   
       2 . The method of  claim 1 , wherein the metal substrate comprises a metal selected from the group consisting of cobalt, cobalt alloys, titanium and titanium alloys.  
   
   
       3 . The method of  claim 1 , wherein the contouring step comprises machining the surface of the porous metal structure.  
   
   
       4 . The method of  claim 1 , wherein the contouring step comprises electro-discharge machining the surface of the porous metal structure.  
   
   
       5 . The method of  claim 1 , wherein the heating step comprises: heating the assembly at about 100° C. to 600° C. for about 1 to 4 hours; and further heating the assembly at about 800° C. to 1600° C. for about one hour to about four hours.  
   
   
       6 . The method of  claim 1 , wherein the heating step is performed in an inert environment comprising a gas selected from the group consisting of argon and helium.  
   
   
       7 . The method of  claim 1 , wherein the heating step is performed in an at least partial vacuum.  
   
   
       8 . A method for attaching a porous metal structure to a metal substrate, the method comprising: 
 providing a metal substrate;    providing the porous metal structure;    contouring a surface of the porous metal structure;    placing the porous structure against the substrate such that the contoured surface of the porous metal structure is disposed against the substrate, thereby forming an assembly; and    applying heat and pressure to the assembly to metallugically bond the porous structure and the substrate.    
   
   
       9 . The method of  claim 8 , wherein the metal substrate comprises a metal selected from the group consisting of cobalt, cobalt alloys, titanium and titanium alloys.  
   
   
       10 . The method of  claim 8 , wherein the contouring step comprises machining the surface of the porous metal structure.  
   
   
       11 . The method of  claim 8 , wherein the contouring step comprises electro-discharge machining the surface of the porous metal structure.  
   
   
       12 . The method of  claim 8 , wherein the heating step comprises: heating the assembly to about 800° C. to 1600° C. for about one hour to about four hours, under a clamping pressure of between about 200 p.s.i. and about 1200 p.s.i.  
   
   
       13 . The method of  claim 8 , wherein the step of applying heat and pressure is in an inert environment comprising a gas selected from the group consisting of argon and helium.  
   
   
       14 . The method of  claim 8 , wherein the step of applying heat and pressure is performed in an at least partial vacuum.  
   
   
       15 . A method for attaching a porous metal structure to a metal component of an orthopedic implant, the method comprising: 
 providing a metal component, having a desired shape and a bone contacting surface;    providing the porous metal structure in a desired shape;    contouring a surface of the porous metal structure;    placing the porous structure against the bone contacting surface of the metal component such that the contoured surface of the porous structure is in contact with the metal component, thereby forming an assembly; and    heating the assembly to metallugically bond the porous structure and the substrate.    
   
   
       16 . A method for attaching a porous metal structure to a metal component of an orthopedic implant, the method comprising: 
 providing a metal component, having a desired shape and a bone contacting surface;    providing the porous metal structure in a desired shape;    contouring a surface of the porous metal structure;    placing the porous structure against the bone contacting surface of the metal component such that the contoured surface of the porous structure is in contact with the metal component, thereby forming an assembly; and    applying heat and pressure to the assembly to metallugically bond the porous structure and the substrate.