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.