Three-dimensional printed composite articles
A 3D object according to the invention comprises substrate layers infiltrated by a 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.
1 . A three-dimensional article of manufacture comprising:
a first plurality of nonwoven carbon fibers in a first layer, each of said first plurality of nonwoven carbon fibers with a first coating in first predetermined locations of the first plurality of nonwoven carbon fibers, said first coating comprising material at a location in the first layer that flowed and hardened into the first coating;
a second plurality of nonwoven carbon fibers in a second layer, each of said second plurality of nonwoven carbon fibers with a second coating in second predetermined locations, said second coating comprising material at a location in the second layer that flowed and hardened into the second coating;
wherein said first coating and said second coating are of a different material from the first plurality of nonwoven carbon fibers and the second plurality of carbon fibers; and
wherein said first layer and said second layer are adjacent, and material of the first or second coating bridges across the first layer to the second layer, or vice versa, into the respective adjacent second or first layer at said first and second predetermined locations to bond said first and second layers together;
and wherein the layers outside said first and second predetermined locations consist of nonwoven carbon fibers that lack said first and second coating and exist in a form that is relatively fragile and friable compared to said first and second coatings and are thus removable at noncoated locations once abraded, abrasively blasted or chemically removed;
whereby said three-dimensional article of manufacture comprises a layered carbon fiber composite object with selected volumes that are hardened and remaining volumes that consist of relatively friable carbon fiber.