Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Electric current delivered to a meniscus of the liquid metal in a quiescent state can be pulsed to reduce the likelihood of formation of an oxidation layer in nozzles associated with these devices, systems, and methods. Such a reduction in the likelihood of formation of an oxidation layer in nozzles can be useful for maintaining integrity of these nozzles between periods of use, such as between formation of parts.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. The magnetohydrodynamic force can be pulsed to eject droplets of the liquid metal to provide control over accuracy of the object being fabricated. The pulsations can be applied in fluid chambers having high resonance frequencies such that droplet ejection can be effectively controlled over a wide range of frequencies, including high frequencies suitable for liquid metal ejection at rates suitable for commercially viable three-dimensional fabrication.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Porosity of one or more predetermined portions of objects fabricated from an accumulation of liquid metal droplets ejected using magnetohydrodynamic force can be controlled to form interfaces between support structures and parts within the object. Higher porosity along the interfaces, as compared to porosity along the support structures and the parts, can be useful for facilitating separation of the parts from the support structures.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. An electric current delivered to produce the magnetohydrodynamic forces can be controlled between a pulsed electric current and a direct electric current to change the rate of liquid metal ejection from a nozzle. For example, the electric current can be switched between a pulsed electric current and a direct electric current based at least in part on a position of the nozzle along the controlled pattern, providing accuracy of liquid metal deposition along portions of the pattern having more detail and providing speed of liquid metal deposition along portions of the pattern having less detail.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Magnets used to form the magnetohydrodynamic forces are thermally managed to facilitate directing strong magnetic fields into liquid metals at high temperatures. Such strong magnetic fields can be useful for imparting, under otherwise equivalent conditions, higher magnetohydrodynamic forces to liquid metal being ejected from a nozzle to form an object.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal from a nozzle along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. A feeder system can provide a continuous or substantially continuous supply of a solid metal to the nozzle to facilitate a correspondingly continuous or substantially continuous process for ejecting liquid metal as part of a commercially viable manufacturing process.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal from a nozzle along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Electrodes used to deliver electric current across a firing chamber of the nozzle are formed of the same material as the liquid metal being ejected from the nozzle. For example, respective interfaces between the electrodes and the liquid metal can be molten material. Forming the electrodes and the liquid metal of the same material can facilitate, for example, ejecting liquid metals having high melt temperatures.

Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Electric current delivered to a meniscus of the liquid metal in a quiescent state can be directed to exert a pullback force on the liquid metal. The pullback force can be sufficient to draw the liquid metal, in the quiescent state, in a direction toward the nozzle to reduce the likelihood of unintended wetting of surfaces of the nozzle between uses of the nozzle.

A print head for an ink jet printer includes at least one ink supply channel and at least one nozzle having a nozzle channel and an inflow opening, and ink can be pressed from the ink supply channel through the inflow opening into the nozzle channel and ejected therefrom, wherein the nozzle is arranged in a stationary manner on a side wall of the ink supply channel and in the ink supply channel a ram is provided, which can be moved back and forth between a reversal point that has a minimal distance from the inflow opening of the nozzle and a reversal point that has a maximal distance from the inflow opening of the nozzle, wherein a first limiting device limits the movement of a ram end face to a movement between the reversal points; and a second external device is provided for applying a negative pressure relative to the ambient air pressure to the ink in the ink supply channel.

The present invention provides a three-dimensional bioprinter for fabricating cellular constructs such as tissues and organs using electromagnetic radiation (EMR) at or above 405 nm. The bioprinter includes a material deposition device comprising a cartridge for receiving and holding a composition which contains biomaterial that cures after exposure to EMR. The bioprinter also includes an EMR module that emits EMR at a wavelength of about 405 nm or higher. Also provided is a bioprinter cartridge which contains cells and a material curable at a wavelength of about 405 nm or greater. The cells are present in a chamber and are extruded through an orifice to form the cellular construct.