Abstract: A plasma arc torch assembly is capable of additively manufacturing articles. A device may additively manufacture at least a portion of an article using the plasma arc torch assembly. A device may deactivate at least one plasma arc associated with the plasma arc torch assembly. A device may perform plasma arc surface smoothing of the article using the plasma arc torch assembly.

Abstract: Wire buffer systems that can buffer one or more wires are described. The wire buffer system can include a buffer tube. The buffer tube can include entry passages, exit passages, an outer cylinder, and an inner cylinder. The inner cylinder can be fixed in a position coaxial with the outer cylinder. Flexible wire guides can be coupled to the entry passage. The flexible wire guide can extend in a spiral around the inner cylinder and exit the buffer tube through the exit passage. The wire buffer systems can further include measurement systems. The measurement systems can include time-of-flight (TOF) sensors, linear rails, and carriages.

Abstract: Cryogenic sources can be used for shielding in wire-based additive manufacturing. Cryogenic shielding can provide better shielding during print, as well as more efficient cooling compared to using regular room temperature shielding gas. Cryogenic shielding can extend the nozzle run time by preventing spatter build up in nozzles. Cryogenic sources also can be used for active part cooling and/or active weld puddle cooling.

Abstract: A device may position a torch assembly relative to a workpiece. A device may initiate a pilot arc between a plasma electrode and a grounded portion of a torch assembly, the grounded portion of the torch assembly grounded using a component with a variable resistance. A device may initiate a wire arc between a first wire element and the workpiece. A device may add material to the workpiece while the torch assembly traverses the workpiece.

Abstract: Systems and methods for localized work return path of additive manufacturing systems are described. Localized grounding connects the printed surface directly to the work return, and shortens the length of grounding and/or the return cables compared to substrate-based grounding.

Abstract: A 3D printer can print a structure by depositing material into a weld pool that is moving relative to a workpiece. A multi-wire process may be utilized to increase the deposition rate of the 3D printer. An electrode wire can supply energy to the weld pool while being fed at a first feed rate into the weld pool. A second wire can be fed into the weld pool at a second feed rate to deposit additional material and thereby speed up the overall material deposition rate. All of the energy in the weld pool may be supplied by the electrode wire. Different materials may benefit from different orientations of the electrode wire and the second wire.

Abstract: Many embodiments described herein are directed to a printing nozzle capable of producing a high-pressure flow of shielding gas that surrounds a lower pressure flow of shielding gas of the central channel. In certain embodiments, the high-pressure shield gas flow in the internal channels can blow out the material buildup in the nozzle. The high-pressure shielding gas can be concentrically produced around the first low-pressure shielding gas such that it helps to force the first shielding gas into a more laminar flow around the feed material. In several embodiments, a second low-pressure flow of shielding gas can be produced using a secondary cup to increase shielding gas coverage. In various embodiments, a secondary cup surrounds the inner cup, where the gas flow in the central channel and the outer channel can provide shielding gas coverage for the nozzle during printing.