Abstract: Systems, methods, components, and materials are disclosed for stereolithographic fabrication of three-dimensional, dense objects. A resin including at least one component of a binder system and dispersed particles can be exposed to an activation light source. The activation light source can cure the at least one component of the binder system to form a green object, which can include the at least one component of the binder system and the particles. A dense object can be formed from the green object by removing the at least one component of the binder system in an extraction process and thermally processing particles to coalesce into the dense object.

Abstract: A method for binder jetting a three-dimensional (3D) object includes receiving a geometry of the object to be printed and generating instructions for printing the object. Generating the instructions includes slicing the geometry of the object into a series of cross-sectional shapes corresponding to where a binder fluid will be deposited onto a powder bed to form the object, and including a plurality of negatively printed features within at least some of the series of cross-sectional shapes, wherein an amount of binder fluid to be deposited in the negatively printed features is less than an amount of binder fluid to be deposited in a remainder of the cross-sectional shape. The amount of binder fluid to be deposited in the negatively printed features and a size of the negatively printed features is configured to allow gas to escape from the powder bed.

Abstract: Disclosed is a method and material system for fabricating metal infiltrated objects having a high volume fraction of infiltrant relative to the infiltrated preform. In an embodiment method, a composite is formed into the shape of a desired object, the composite including a skeletal phase and a fugitive phase. The fugitive phase is then removed to create a self-supporting porous skeletal structure. The porous skeletal structure is then infiltrated with the infiltrant to achieve a densified object.

Abstract: A method of maintaining part geometry fidelity during infiltration of a metallic preform. The preform and an infiltration barrier are formed, either independently or together during an additive manufacturing process. The infiltration barrier prevents infiltrant from bleeding out from the preform where it is present, thus protecting fine geometries that would otherwise be filled with infiltrant.

Abstract: Materials, designs, and methods of fabrication for iron-manganese oxide electrochemical cells are disclosed. In various embodiments, the negative electrode is comprised of pelletized, briquetted, or pressed iron-bearing components, including metallic iron or iron-based compounds (oxides, hydroxides, sulfides, or combinations thereof), collectively called “iron negative electrode.” In various embodiments, the positive electrode is comprised of pelletized, briquetted, or pressed manganese-bearing components, including manganese (IV) oxide (MnO2), manganese (III) oxide (Mn2O3), manganese (III) oxyhydroxide (MnOOH), manganese (II) oxide (MnO), manganese (II) hydroxide (Mn(OH)2), or combinations thereof, collectively called “manganese oxide positive electrode.” In various embodiments, electrolyte is comprised of aqueous alkali metal hydroxide including lithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), cesium hydroxide (CsOH), or combinations thereof.

Abstract: Systems and methods of the various embodiments may provide low cost bifunctional air electrodes. Various embodiments may provide a bifunctional air electrode, including a metal substrate and particles of metal and/or metal oxide catalyst and/or metal nitride catalyst coated on the metal substrate. Various embodiments may provide a bifunctional air electrode, including a first portion configured to engage an oxygen reduction reaction (ORR) in a discharge mode and a second portion configured to engage an oxygen evolution reaction (OER) in a charge mode. Various embodiments may provide a method for making an air electrode including coating a metal substrate with particles of metal and/or metal oxide catalyst and/or metal nitride catalyst. Various embodiments may provide batteries including air electrodes.

Abstract: Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Porosity of one or more predetermined portions of objects fabricated from an accumulation of liquid metal droplets ejected using magnetohydrodynamic force can be controlled to form interfaces between support structures and parts within the object. Higher porosity along the interfaces, as compared to porosity along the support structures and the parts, can be useful for facilitating separation of the parts from the support structures.

Abstract: Materials and methods are disclosed for forming interface layers between objects being 3D printed and their underlying support structures, as well as dissolvable supports. The materials and methods facilitate separation of the objects from the supports after all processing is completed and are particularly useful when 3D printing metal objects that have to be sintered subsequent to 3D printing.

Abstract: An additive manufacturing method including depositing a first amount of metal powder on a print bed, the first amount metal powder forming a first layer, depositing a first binder component to the first layer in a first region, and depositing a second binder component to the first layer in a second region.

Abstract: The present invention relates to a shrinking interface composition that allows for the accommodation of sintering shrinkage between two or more areas or sections of a three-dimensionally printed part and/or support structures for the part. The interface composition, which can be in the form of an interface layer, is used to prevent the fusing of the sections, parts or support structures to each other.

Abstract: A variety of additive manufacturing techniques can be adapted to fabricate a substantially net shape object from a computerized model using materials that can be debound and sintered into a fully dense metallic part or the like. However, during sintering, the net shape will shrink as binder escapes and the base material fuses into a dense final part. If the foundation beneath the object does not shrink in a corresponding fashion, the resulting stresses throughout the object can lead to fracturing, warping or other physical damage to the object resulting in a failed fabrication. To address this issue, a variety of techniques are disclosed for substrates and build plates that contract in a manner complementary to the object during debinding and sintering.

Abstract: A three-dimensional printer includes a vessel containing a liquid in which a printed object can debind during fabrication. More generally, the vessel may contain any liquid medium selected to control or modify properties of a printed object during fabrication. For example, the liquid may also or instead impose a controlled thermal environment for the printed object, apply finishing materials to an exterior surface of the object, provide a component or catalyst for a reaction, or otherwise treat the printed object or control ambient conditions during printing.

Abstract: Support structures are used in certain additive fabrication processes to permit fabrication of a greater range of object geometries. For additive fabrication processes with materials that are subsequently sintered into a final part, an interface layer is fabricated between the object and support in order to inhibit bonding between adjacent surfaces of the support structure and the object during sintering. Interface layers suitable for manufacture with an additive manufacturing system may resist the formation of bonds between a support structure and an object during subsequent sintering processes.

Abstract: In an aspect, multiple metallic base materials are mixed into a user-controlled multimetallic mixture and extruded into a net shape, which is thermally processed into a multimetallic and/or alloyed object. In another aspect, a superstructure is fabricated around an object, but physically isolated from the object, with a shape facilitating robotic handling of the superstructure, along with removal of powder from the object, after a three-dimensional printing process. In another aspect, a ceramic precursor is used to create a separable interface between a support structure and a sinterable object. More specifically, a sinterable structure is fabricated from a sinterable powder in an aqueous binder, and an interface layer is formed by depositing a ceramic precursor in a nonaqueous solution onto the sinterable structure. When the ceramic precursor is exposed to water in the aqueous binder, the ceramic can precipitate to form an unsinterable, ceramic interface layer between sinterable structures.

Abstract: Support structures are used in certain additive fabrication processes to permit fabrication of a greater range of object geometries. For additive fabrication processes with materials that are subsequently sintered into a final part, an interface layer is formed between the object and support in order to inhibit bonding between adjacent surfaces of the support structure and the object during sintering. The support structure may be a multi-part support structure to mitigate mold lock or facilitate removal from enclosed spaces.

Abstract: Techniques are disclosed for fabricating multi-part assemblies. In particular, by forming release layers between features such as bearings or gear teeth, complex mechanical assemblies can be fabricated in a single additive manufacturing process.

Abstract: Devices, systems, and methods are directed to binder jetting for forming three-dimensional parts having controlled, macroscopically inhomogeneous material composition. In general, a binder may be delivered to each layer of a plurality of layers of a powder of inorganic particles. An active component may be introduced, in a spatially controlled distribution, to at least one of the plurality of layers such that the binder, the powder of inorganic particles, and the active component, in combination, form an object. The object may be thermally processed into a three-dimensional part having a gradient of one or more physicochemical properties of a material at least partially formed from thermally processing the inorganic particles and the active component of the object.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. The shape of an extrusion nozzle may be varied during extrusion to control, e.g., an amount of build material deposited, a shape of extrudate exiting the nozzle, a feature resolution, and the like.

Abstract: Additive fabrication systems generally use support structures to expand the available range of features and geometries in fabricated objects. For example, when a vertical shelf or cantilever extends from an object, a supplemental support structure may be required to provide a surface for fabrication thereon. This process may become more difficult when, e.g., a part will be subjected to downstream processing steps such as debinding or sintering that impose different design rules. To address these challenges and provide a greater range of flexibility and processing speed, it may be useful in certain circumstances to independently fabricate the object and support structures, and then assemble these structures into a composite item for debinding and sintering. This approach also advantageously facilitates various techniques for spraying, dipping, or otherwise applying a release layer between the support structure and the part so that these separate items do not become fused together during sintering.

Abstract: Techniques and compositions are disclosed for composite feedstocks with powder/binder systems suitable for three-dimensional printing, such as fused filament fabrication. The composite feedstocks may include a jacket about a core, with at least the core including a powder material suspended in a binder system and the jacket having a hardness or toughness greater than a hardness or toughness of the core for the feedstock. In general, the harder jacket may protect the core from unintended deformation or damage during transportation, storage, or use. For example, the difference in hardness or toughness between the jacket and the core may facilitate gripping the feedstock (e.g., by gear drives or the like) with a higher amount of force than is otherwise applicable if the feedstock were composed of the core alone, without damaging the core, during a fused filament fabrication process or another additive manufacturing process.