Solidification refinement and general phase transformation control through application of in situ gas jet impingement in metal additive manufacturing

A jet device, comprising:

• a first conduit comprising:
• a first inlet for accepting a cooling gas;
• and
• a first aperture connected to a first nozzle for dispensing the cooling gas;
• and
• a second conduit comprising:
• a second inlet for accepting the cooling gas;
• and
• a second aperture connected to a second nozzle for dispensing the cooling gas;
• wherein:
• the first conduit is attached to a melting tool on a first side of a thermal energy source produced by the melting tool and the second conduit is attached to the melting tool on an opposite, second side of the thermal energy source;
• at least one of the first nozzle or second nozzle is configured to produce a turbulent flow of the cooling gas as the cooling gas is dispensed during material deposition;
• the first nozzle and second nozzle are configured to direct the cooling gas to impinge on one or more of a molten pool and a liquid-solid boundary of the molten pool;
• and
• the first nozzle and second nozzle are positioned to prevent blowing the cooling gas toward the thermal energy source.