Particulates for additive manufacturing techniques

Abstract

A particulate for an additive manufacturing technique includes a particulate body formed from a particulate material and a coating disposed over particulate body. The coating includes a carbonaceous material that has a reflectivity that is lower than a reflectivity of the particulate material to reduce an energy input requirement of the particulate such that less energy is necessary to fuse the particulate into a layer of an article fabricated using the additive manufacturing technique. A method of making particulate is also disclosed.

What is claimed is: 
     
         1 . A method of additive layer manufacturing, the method comprising:
 receiving particulate at a chemical vapor deposition (CVD) reactor;   flowing a hydrocarbon gas into the CVD reactor;   decomposing the hydrocarbon gas in the CVD reactor;   depositing a carbonaceous coating on the particulate using a product of the decomposed hydrocarbon gas, wherein the coating has a reflectivity that is lower than a reflectivity the underlying particulate body to reduce an energy input requirement of the particulate to fuse the particulate into a layer of an article using an additive manufacturing technique; and   receiving coated particulate at an additive manufacturing apparatus, and fusing the coated particulate into a layer of an article using a high density energy source.   
     
     
         2 . A method as recited in  claim 1 , wherein depositing the carbonaceous coating on the particulate includes depositing a carbonaceous layer including graphene or carbon nanotubes on a surface of the particulate in the CVD reactor. 
     
     
         3 . A layer formed from the method of  claim 1 , comprising:
 a particulate body formed from a particulate material; and   a coating disposed over at least a portion of the particulate body and formed from a carbonaceous material, wherein the coating has a reflectivity that is lower than a reflectivity of the underlying particulate body to reduce an energy input requirement of the particulate to fuse the particulate into a layer of an article using an additive manufacturing technique.   
     
     
         4 . A layer as recited in  claim 3 , wherein the particulate body includes a metallic material. 
     
     
         5 . A layer as recited in  claim 3 , wherein the particulate body includes at least one of aluminum, copper, nickel, iron, titanium, molybdenum, alloys thereof, and ceramic. 
     
     
         6 . A layer as recited in  claim 3 , wherein the carbonaceous material includes graphene and/or carbon nanotubes. 
     
     
         7 . A layer as recited in  claim 3 , wherein the coating material has an electrical resistivity that is lower than an electrical resistivity of the particulate body. 
     
     
         8 . A layer as recited in  claim 3 , wherein the coating material has a thermal conductivity that is greater than a thermal conductivity of the particulate body. 
     
     
         9 . A layer as recited in  claim 3 , wherein the particulate body includes a particulate first material and a particulate second material, the particulate first material having an electrical resistivity that is lower than an electrical resistivity of the particulate second material, wherein the coating material has an electrical resistivity that is lower than the electrical resistivity of the particulate second material. 
     
     
         10 . A layer as recited in  claim 9 , wherein the electrical resistivity of the coating material is lower than the electrical resistivity of both the first and particulate second materials. 
     
     
         11 . A layer as recited in  claim 3 , wherein the particulate body includes a particulate first material and a particulate second material, the particulate first material having a thermal conductivity that is greater than a thermal conductivity of the particulate second material, wherein the coating material has a thermal conductivity that is greater than the thermal conductivity of the particulate second material. 
     
     
         12 . A layer as recited in  claim 11 , wherein the thermal conductivity of the particulate first material is greater than the thermal conductivity of the particulate second material. 
     
     
         13 . A layer as recited in  claim 3 , wherein the particulate material includes copper and phosphorus.