Support structure for a fabricated object

Abstract

A support structure is formed from a support material below a printed object that shrinks similarly to a build material of the printed object during processing in a furnace.

What is claimed is: 
     
         1 . An article comprising:
 an object formed of a build material including a metal powder sinterable into a final dense part and a binder system including a polymeric binder that carries the metal powder into position within a print and retains the metal powder in a net shape for the object during a fused filament fabrication process, wherein the binder system has a metal loading with the metal powder of at least fifty percent by volume;   a support structure underneath the object and formed from a support material to provide a physical support to the object during printing and sintering, wherein the support structure supports the object where there is no underlying physical surface of the object upon which a material can be deposited during fabrication, and further wherein the support structure shrinks similarly to the build material during processing in a furnace; and   an interface material between the object and the support structure, the interface material including a ceramic that will not sinter under time and temperature conditions used to sinter the build material in the object.   
     
     
         2 . The article of  claim 1  wherein the support structure resists a force of extrusion during the fused filament fabrication process, and wherein the support structure resists forces of gravity on the object during a sintering process. 
     
     
         3 . The article of  claim 1  wherein the binder system has a metal loading with the metal powder of at least sixty percent by volume. 
     
     
         4 . An article comprising:
 an object formed of a build material including a metal powder sinterable into a final dense part and a binder system that carries the metal powder into position within a print and retains the metal powder in a net shape for the object;   a support structure for the object, the support structure formed from a support material to provide a physical support to the object during printing and sintering, wherein the support structure shrinks similarly to the build material during processing in a furnace; and   an interface material forming a non-sinterable layer between the object and the support structure.   
     
     
         5 . The article of  claim 4  wherein the support structure supports the object where there is no underlying physical surface of the object upon which a material can be deposited during fabrication. 
     
     
         6 . The article of  claim 4  wherein the support structure provides vertical support to the object. 
     
     
         7 . The article of  claim 4  wherein the support structure supports a horizontal surface of the object. 
     
     
         8 . The article of  claim 4  wherein the support structure includes a side support. 
     
     
         9 . The article of  claim 4  wherein the support structure includes a top support. 
     
     
         10 . The article of  claim 4  wherein the support structure includes a print support that is removed after printing. 
     
     
         11 . The article of  claim 4  wherein the support structure includes a sintering support that is left attached to the object until sintering is at least sufficiently completed to eliminate a need for the support structure. 
     
     
         12 . An article comprising:
 an object formed of a build material including a metal powder sinterable into a final dense part and a binder system that carries the metal powder into position within a print and retains the metal powder in a net shape for the object; and   a support structure for the object and formed from a support material to provide a physical support to the object during printing and sintering, wherein the support structure shrinks similarly to the build material during processing in a furnace.   
     
     
         13 . The article of  claim 12  further comprising an interface material between the object and the support structure. 
     
     
         14 . The article of  claim 13  wherein the interface material forms a non-sinterable layer between the object and the support structure. 
     
     
         15 . The article of  claim 13  wherein the interface material will not sinter under time and temperature conditions used to sinter the build material. 
     
     
         16 . The article of  claim 13  wherein the interface material includes a ceramic. 
     
     
         17 . The article of  claim 12  wherein the metal powder of the build material includes at least one of stainless steel, tungsten, titanium, titanium alloy, high-nickel alloy, and nickel copper alloy. 
     
     
         18 . The article of  claim 12  wherein the binder system includes a polymer binder that is flexible at room temperature. 
     
     
         19 . The article of  claim 12  wherein the metal powder has a powder size of between one and twenty microns. 
     
     
         20 . The article of  claim 12  wherein the binder system as a metal loading of at least fifty percent by volume of the metal powder. 
     
     
         21 . The article of  claim 12  wherein the metal powder has an average diameter of between about five microns and about eighty microns.