Method for Fabricating Three-Dimensional Printed Composites

Abstract

A 3D object according to the invention comprises substrate layers infiltrated by hardened material. The 3D object is fabricated by a method comprising the following steps: Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Stack the substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers. In a preferred embodiment, the substrate is carbon fiber and excess substrate is removed by abrasion.

We claim: 
     
         1 . A three-dimensional (3D) object fabricated by the process:
 selectively depositing an adhering agent in a desired pattern onto portions of a sheet comprising substrate material wherein the desired pattern corresponds to a layer of the 3D object;   applying powder onto the sheet, whereby the powder adheres to the sheet only at locations of the desired pattern;   removing non-adhering powder to form a coated substrate sheet; and   stacking and aligning a plurality of coated substrate sheets to form a stack of coated substrate sheets;   applying pressure to the stack of coated substrate sheets;   applying heat to the stack of coated substrate sheets;   removing at least some regions of the coated substrate sheets where the adhering agent has not been deposited;   the 3D object comprising:   a stack of coated substrate sheets comprising adhering powder and substrate material from each coated substrate sheet fused to adhering powder and substrate material from adjacent coated substrate sheets to form the 3D object.   
     
     
         2 . The 3D object of  claim 1 , wherein said pressure is applied using an artificial pressure source. 
     
     
         3 . The 3D object of  claim 2 , wherein the artificial pressure source is chosen from the group consisting of a press, clamp, iron, roller, pump, piston, or spring. 
     
     
         4 . The 3D object of  claim 1 , wherein the adhering powder is a thermoplastic. 
     
     
         5 . The 3D object of  claim 1 , wherein a stacking apparatus is used for stacking and aligning the plurality of coated substrate sheets. 
     
     
         6 . The 3D object of  claim 5 , wherein the stacking apparatus comprises registration pins. 
     
     
         7 . The 3D object of  claim 1 , wherein the removing is done by abrasive blasting. 
     
     
         8 . The 3D object of  claim 7 , wherein the abrasive blasting is done using an abrasive material which comprises one or more of garnet, glass beads, glass grit, aluminum oxide, silicon carbide, carborundum, ceramic shot, ceramic grit, steel shot, steel grit, cut wire, copper shot, aluminum shot, zinc shot, copper slag, nickel slag, magnesium sulfate, kieserite, staurolite, sodium bicarbonate, dry ice, plastic abrasive, or crushed nut shells. 
     
     
         9 . The 3D object of  claim 7 , wherein an abrasive medium used during the abrasive blasting is propelled by a pressurized fluid. 
     
     
         10 . The 3D object of  claim 1  wherein the sheet is a non-woven material. 
     
     
         11 . The 3D object of  claim 9 , wherein the pressurized fluid is water or air. 
     
     
         12 . The 3D object of  claim 7 , wherein an abrasive medium used during abrasive blasting is propelled by a moving object. 
     
     
         13 . The 3D object of  claim 12 , wherein the moving object is a rotating wheel. 
     
     
         14 . The 3D object of  claim 1  further comprising internal channels. 
     
     
         15 . The 3D of  claim 7  further comprising internal channels, wherein the abrasive blasting is used to clear the internal channels in the three-dimensional object. 
     
     
         16 . The 3D object  claim 1 , wherein the substrate material comprises carbon fiber. 
     
     
         17 . A three-dimensional (3D) object fabricated by the process:
 selectively depositing an adhering agent in a desired pattern onto portions of a sheet comprising substrate material wherein the desired pattern corresponds to a layer of the 3D object;   applying powder onto the sheet, whereby the powder adheres to the sheet only at locations of the desired pattern;   removing non-adhering powder to form a coated substrate sheet; and   stacking and aligning a plurality of coated substrate sheets to form a stack of coated substrate sheets;   applying pressure to the stack of coated substrate sheets;   applying heat to the stack of coated substrate sheets;   removing at least some regions of the coated substrate sheets where the adhering agent has not been deposited;   the 3D object comprising:   a stack of coated substrate sheets comprising adhering powder and substrate material from each coated substrate sheet fused to adhering powder and substrate material from adjacent coated substrate sheets to form the 3D object;   wherein at least some of the powder on a substrate sheet has flowed and subsequently hardened into hardened material, thereby binding at least some of the coated substrate sheets together, wherein the hardened material is disposed in a spatial pattern that defines at least one positive region in the stacked plurality of coated substrate sheets, and is absent from at least one negative region in the plurality of coated substrate sheets, the three-dimensional object comprising the stacked and bound coated substrate sheets comprising the spatial pattern of hardened material.   
     
     
         18 . The 3D object of  claim 16 , wherein the powder is caused to flow by applying heat. 
     
     
         19 . The 3D object  claim 16 , wherein the substrate material comprises carbon fiber.