In one example in accordance with the present disclosure, a build material volume transportation device is described. The build material volume transportation device includes a shuttle to transport a build material volume. The shuttle includes an opening therethrough to receive the build material volume. The build material volume transportation device also includes a build tray to raise the build volume into the opening in the shuttle. The build material volume transportation device further includes a latch assembly to releasably secure the build tray to the shuttle. A tip of the latch assembly extends to interface with the aperture to secure the build tray to the shuttle. The tip rotates independently of the piston.

The devices and systems described herein generally relate to magnetic field chambers and reversibly hardenable ferrofluids. The reversibly hardenable ferrofluid can include a magnetically responsive fluid and a reversible hardening agent. The reversibly hardenable ferrofluid can achieve a first shape using one or more magnetic fields, such as delivered from a magnetic field chamber. Once the first shape is achieved, the reversibly hardenable ferrofluid can be cured or otherwise hardened. The hardened reversibly hardenable ferrofluid can be used for the intended purpose and then returned to a liquid state once the task is completed, allowing for reuse. The steps of hardening and liquifying can be mediated by the magnetic field chamber, as described in embodiments herein.

The devices and systems described herein generally relate to magnetic field chambers and reversibly hardenable ferrofluids. The reversibly hardenable ferrofluid can include a magnetically responsive fluid and a reversible hardening agent. The reversibly hardenable ferrofluid can achieve a first shape using one or more magnetic fields, such as delivered from a magnetic field chamber. Once the first shape is achieved, the reversibly hardenable ferrofluid can be cured or otherwise hardened. The hardened reversibly hardenable ferrofluid can be used for the intended purpose and then returned to a liquid state once the task is completed, allowing for reuse. The steps of hardening and liquifying can be mediated by the magnetic field chamber, as described in embodiments herein.

A method, system, and apparatus for fabricating an acoustic metamaterial is provided. In an embodiment, a method for fabricating an acoustic metamaterial includes determining at least one tuned physical property for each of a plurality of micro-resonators according to a desired acoustic property of the acoustic metamaterial. For a particular physical property, a value of the tuned physical property for at least one of the plurality of micro-resonators is different from a value of the tuned physical property for at least one other of the plurality of micro-resonators. The method also includes additively forming the acoustic metamaterial such that the acoustic metamaterial comprises a first structure and the plurality of micro-resonators embedded within the first structure. Forming the acoustic metamaterial is performed such that an actual physical property of each of the plurality of micro-resonators is equal to a corresponding tuned physical property for each of the plurality of micro-resonators.

A method, system, and apparatus for fabricating an acoustic metamaterial is provided. In an embodiment, a method for fabricating an acoustic metamaterial includes determining at least one tuned physical property for each of a plurality of micro-resonators according to a desired acoustic property of the acoustic metamaterial. For a particular physical property, a value of the tuned physical property for at least one of the plurality of micro-resonators is different from a value of the tuned physical property for at least one other of the plurality of micro-resonators. The method also includes additively forming the acoustic metamaterial such that the acoustic metamaterial comprises a first structure and the plurality of micro-resonators embedded within the first structure. Forming the acoustic metamaterial is performed such that an actual physical property of each of the plurality of micro-resonators is equal to a corresponding tuned physical property for each of the plurality of micro-resonators.

A machine and method of forming an article generally comprising extruding a molten bead of thermoplastic material along x, y and z axes in forming an article consisting of a strata of such material, and passing a roller over each applied portion of such molten bead to compress such bead portion, enhancing the fusion of engaging plies of such extruded material.

A machine and method of forming an article generally comprising extruding a molten bead of thermoplastic material along x, y and z axes in forming an article consisting of a strata of such material, and passing a roller over each applied portion of such molten bead to compress such bead portion, enhancing the fusion of engaging plies of such extruded material.

A method of making a foamed article comprises (a) injection molding a molten thermoplastic elastomer to form an precursor; (b) crosslinking the thermoplastic elastomer; (c) heating the thermoplastic elastomer to a first temperature to soften the thermoplastic elastomer; (d) infusing the thermoplastic elastomer with at least one inert gas at a first pressure that is sufficient to cause the at least one inert gas to permeate into the softened thermoplastic elastomer; and (e) while the article is softened, reducing the pressure to a second pressure below the first pressure to at least partially foam the precursor into a foamed article, wherein the foamed article is substantially the same shape as the precursor.

A method of making a foamed article comprises (a) injection molding a molten thermoplastic elastomer to form an precursor; (b) crosslinking the thermoplastic elastomer; (c) heating the thermoplastic elastomer to a first temperature to soften the thermoplastic elastomer; (d) infusing the thermoplastic elastomer with at least one inert gas at a first pressure that is sufficient to cause the at least one inert gas to permeate into the softened thermoplastic elastomer; and (e) while the article is softened, reducing the pressure to a second pressure below the first pressure to at least partially foam the precursor into a foamed article, wherein the foamed article is substantially the same shape as the precursor.

Devices, systems, and methods are directed to the use of vapor phase change in binder jetting processes for forming three-dimensional objects. In general, a vapor of a first fluid may be directed to a layer of a powder spread across a build volume. The vapor may condense to reduce mobility of the particles of the powder of the layer. For example, the condensing vapor may reduce the likelihood of particle ejection from the layer and, thus, may reduce the likelihood of clogging or otherwise degrading a printhead used to jet a second fluid (e.g., a binder) to the layer. Further, or instead, the condensing vapor may increase the density of the powder in the layer which, when repeated over a plurality of layers forming a three-dimensional object, may reduce the likelihood of slumping of the part during sintering.