Abstract: A method for manufacturing a monolithic multi-material article is provided. A first metallic material including copper is deposited to form a first portion. A second metallic material including a ferrous alloy is deposited onto the first portion to form a second portion. The portions are metallurgically bonded to create a single article. The first portion may be machined before over-deposition; the first portion can be maintained at 200-600° C. during deposition of the ferrous alloy. Representative parameter ranges include laser power 200-5000 W, traverse speed 200-2000 mm/min, energy density 30-200 J/mm3, and mass flow 5-50 g/min. Deposition can be performed with argon and/or helium shielding in an inert atmosphere with oxygen below 100 ppm. Ferrous alloys can include precipitation-hardenable stainless steels. The article can be a cooling insert for a mold or die.

Abstract: A hybrid electroslag additive manufacturing method is provided. This hybrid method combines the benefits of wire-arc additive manufacturing with the benefits of electroslag welding and casting. As discussed herein, the hybrid method employs an interleaved wall-and-infill strategy, wherein the wall is manufacturing via wire-arc additive manufacturing or other directed energy deposition, and the infill is provided by electroslag welding/casting techniques or similar processes, such as submerged arc welding. The hybrid method can produce large, complex components at higher rates with lower lead times than either of the techniques individually.

Abstract: A multi material extrusion system includes a first polymer extruder configured to extrude a first polymer, and a second polymer extruder configured to extrude a second polymer. A nozzle includes a first polymer inlet in fluid connection with the first extruder, a second polymer inlet in fluid connection with the second extruder, and a merging nozzle conduit having a merging nozzle conduit surface. The merging nozzle conduit terminates in a merging nozzle conduit outlet opening. The nozzle further includes a first polymer flow conduit in fluid communication with the first polymer inlet and a second polymer flow conduit in fluid communication with the second polymer inlet. The first polymer flow conduit is configured to deliver the first polymer to the merging nozzle conduit and the second polymer flow conduit is configured to deliver the second polymer to the merging nozzle conduit, to create a multi-material bead comprising the first polymer in contact with the second polymer.

Abstract: A method of forming an additively manufactured part includes: converting a desired final three-dimensional part geometry into a flattened, computer-modeled shape; operating a printhead to deposit a first layer of a part-forming material on a substrate, the first layer being one of a plurality of iteratively deposited layers of an additive build according to the flattened, computer-modeled shape, such that the additive build is comprised of successive layers of the deposited part material on the substrate; and creating a part by manipulating one or more portions of the additive build at one or more predetermined locations to form the additive build into a final shape having the desired final three-dimensional part geometry. The part-forming material and the substrate each may include a thermoset or thermoplastic, and may include a curable resin. The substrate may be in the form of an impregnated or unimpregnated sheet, film, fabric, laminated fabric, or weave.

Abstract: An additive manufacturing system for additive manufacturing material with long fibers includes an extruder comprising a nozzle that includes a static-mixing portion, a compression portion, and a long fiber alignment portion. The static-mixing portion includes a static-mixing channel with static-mixing rods distributed inside and extending radially inward from a channel wall. The long fiber alignment portion has an alignment channel with a diameter DAC that is less than a diameter DSMC of the static-mixing channel. The compression portion includes with a reducing diameter from an input end to an output end of the compression channel. A nozzle and method for additive manufacturing are also disclosed.

Abstract: A system and method of making an additively manufactured, metal near net shape part includes introducing a metallic-element-bearing feedstock into a melt zone of an additive manufacturing printhead. The metallic-element-bearing feedstock is mixed in the melt zone with a flux composition to form a slag bath mixture upon melting. The metallic-element-bearing feedstock is refined in-situ by melting the slag bath mixture with the application of thermal energy to the slag bath mixture to form a phase-separated product including a slag phase and a metal-rich liquid phase. The metal-rich liquid phase is simultaneously deposited to form a first metal layer that is one of a plurality of iteratively deposited metal layers of an additive build according to a three-dimensional digital model. The additive build has successive layers of the deposited, solidified metal-rich liquid that form a near net shape metallic part.

Abstract: Systems and methods for operating an aquatic robot. The methods comprise: autonomously propelling the aquatic robot through a body of water to a location where a water sample is to be obtained; and performing operations by the aquatic robot to autonomously collect the water sample, cause the water sample to flow through a filter that retains eDNA, lyses and releases the eDNA to a create a lysate, process the lysate to obtain a product for eDNA sequencing, generate eDNA sequencing data using the product, and communicate the eDNA sequencing data to a remote external device.

Abstract: An additive manufacturing system for additive manufacturing with an additive manufacturing material and fibers includes an extruder comprising a static-mixing nozzle having a static-mixing channel and static-mixing structures distributed inside the static-mixing channel and extending radially inward from the channel wall, and being longitudinally distributed and radially staggered over a portion of the length of the static-mixing channel. A static-mixing nozzle, a method of additive manufacturing, and a method of making a static mixing nozzle for additive manufacturing are also disclosed.

Abstract: An additive manufacturing system for additive manufacturing material with long fibers includes an extruder comprising a nozzle that includes a static-mixing portion, a compression portion, and a long fiber alignment portion. The static-mixing portion includes a static-mixing channel with static-mixing rods distributed inside and extending radially inward from a channel wall. The long fiber alignment portion has an alignment channel with a diameter DAC that is less than a diameter DSMC of the static-mixing channel. The compression portion includes with a reducing diameter from an input end to an output end of the compression channel. A nozzle and method for additive manufacturing are also disclosed.

Abstract: Systems and methods for operating an aquatic robot. The methods comprise: autonomously propelling the aquatic robot through a body of water to a location where a water sample is to be obtained; and performing operations by the aquatic robot to autonomously collect the water sample, cause the water sample to flow through a filter that retains eDNA, lyses and releases the eDNA to a create a lysate, process the lysate to obtain a product for eDNA sequencing, generate eDNA sequencing data using the product, and communicate the eDNA sequencing data to a remote external device.

Abstract: An electromagnet alignment system for in-situ alignment of a magnetic particulate material is provided. The magnetic particulate material is dispensed through an orifice of a dispensing nozzle used for 3D printing. The system has an electromagnet assembly having a coil. The coil is configured to generate a pulsed magnetic field having a target magnetic flux intensity upon energization of the coil when the magnetic particulate material is being heated and moved through the dispensing nozzle. As a result, the magnetic particulate material is at least partially aligned with respect to a direction by the pulsed magnetic field. The system further includes a power source for implementing the energization of the coil.

Abstract: A print head for additive manufacturing with a material includes an accumulator comprising an elongated body with an open interior and an inside diameter. A slide tube is slidably mounted within the open interior of the elongated body. The slide tube has a sealing piston head hermetically sealing the open end within the elongated body to define a variable gas containment space. A pressurized gas is supplied to the gas containment space. A rotatable shaping nozzle with an opening for discharging material is provided. A positive displacement extruder delivers material from the accumulator to the nozzle assembly. The nozzle assembly can include a nozzle rotation drive for rotating the shaping nozzle about an axis of rotation. The nozzle opening can be aligned with the axis of rotation, and defines a discharge axis that can be perpendicular to the axis of rotation. A method of additive manufacturing is also disclosed.

Abstract: Toolpath generation for additive manufacturing systems involves operations on polygonal contours derived from a model for additively manufacturing a structure. One aspect involves modifying or creating a model to allow parts to be printed without starting and stopping the printing equipment by generating continuous toolpaths or toolpaths having a reduced number of isolated paths. Another aspect involves modifying a slicing engine to generate a continuous toolpath or toolpath having a reduced number of isolated paths based on a representation of an object to be additively manufactured. Another aspect involves selectively placing the gaps at alternating positions among the sliced layers to create a zippering effect.

Abstract: A system and method for improving additive manufacturing, including additive manufacturing toolpaths, is provided. The system and method includes a toolpath generator that obtains initial toolpaths of an object, identifies isolated paths in the toolpaths, and adds bridge connections between neighboring isolated paths in each layer to improve the toolpaths. The bridge connections facilitate the continuous and non-stop deposition of each layer according to improved toolpaths during additive manufacture, which can reduce total deposition time and improve the resultant additive manufacture.

Abstract: A method for rapid manufacturing of three dimensional discontinuous fiber preforms is provided. The method includes the deposition of a polymeric material containing fibers on a surface to form a tailored charge for compression molding. The reinforced polymeric material may be a thermoplastic or a reactive polymer with viscosity low enough to allow flow through an orifice during deposition, yet high enough zero shear viscosity to retain the approximate shape of the deposited charge. The material can be deposited in a predetermined pattern to induce the desired mechanical properties through alignment of the fibers. This deposition can be performed in a single layer or in multiple layers. The alignment is achieved passively by shear alignment of the fibers or actively through fiber orientation control or mixing. The fibers can be of the desired material, length, and morphology, including short and long filaments.

Abstract: A print head for additive manufacturing with a material includes an accumulator comprising an elongated body with an open interior and an inside diameter. A slide tube is slidably mounted within the open interior of the elongated body. The slide tube has a sealing piston head hermetically sealing the open end within the elongated body to define a variable gas containment space. A pressurized gas is supplied to the gas containment space. A rotatable shaping nozzle with an opening for discharging material is provided. A positive displacement extruder delivers material from the accumulator to the nozzle assembly. The nozzle assembly can include a nozzle rotation drive for rotating the shaping nozzle about an axis of rotation. The nozzle opening can be aligned with the axis of rotation, and defines a discharge axis that can be perpendicular to the axis of rotation. A method of additive manufacturing is also disclosed.

Abstract: An assembly for additive manufacturing includes a build housing including a base, a print head, and a print head support connected to the base for supporting the print head above the base. A driver system is provided for moving the print head and the base relative to one another. A build platform comprising a build support and at least one platen. The build support can be detachably engageable to the housing. The platens can be detachably engageable to the build support. The build support can include registration structure for registering the position of the build support relative to the build housing. A method of additive manufacturing is also disclosed.

Abstract: A cable-driven additive manufacturing system includes an end effector configured for linear translation within a three-dimensional workspace, an aerial hoist suspending the end effector by at least one suspension cable, a plurality of base stations disposed below the aerial hoist, and control cables running from each of the base stations to the end effector.

Abstract: An electromagnet alignment system for in-situ alignment of a magnetic particulate material is provided. The magnetic particulate material is dispensed through an orifice of a dispensing nozzle used for 3D printing. The system has an electromagnet assembly having a coil. The coil is configured to generate a pulsed magnetic field having a target magnetic flux intensity upon energization of the coil when the magnetic particulate material is being heated and moved through the dispensing nozzle. As a result, the magnetic particulate material is at least partially aligned with respect to a direction by the pulsed magnetic field. The system further includes a power source for implementing the energization of the coil.

Abstract: A method of forming a low-density three-dimensional article is provided. The method includes printing a low-density composition on a substrate to form at least one layer comprising the low-density composition. The low-density composition includes a (P) polymer component and (M) a microsphere component in a ratio by volume (P):(M). The method also includes selectively controlling a density of the low-density composition during printing to give the at least one layer on the substrate. Selectively controlling the density of the low-density composition includes varying the ratio (P):(M) during printing. The method further includes repeating the printing and selectively controlling the density of the low-density composition to form additional layer(s), thereby forming the low-density three-dimensional article. A low-density three-dimensional article prepared in accordance with the method is also provided.