A three-dimensional (3D) printer build material spreader cooling system may include a build volume, a build material spreader, a spreader drive, a spreader cooler and a cooling fluid supply. The build material spreader may have a length and a first fluid conduit extending along the length. The spreader drive is to translate the build material spreader across the build volume. The spreader cooler is in thermal conductive contact with the build material spreader. The spreader cooler has a second fluid conduit extending along the length. The cooling fluid supply directs cooling fluid in a first direction through the first fluid conduit and in a second direction, opposite the first direction, through the second fluid conduit.

A three-dimensional (3D) printer build material spreader cooling system may include a build volume, a build material spreader, a spreader drive, a spreader cooler and a cooling fluid supply. The build material spreader may have a length and a first fluid conduit extending along the length. The spreader drive is to translate the build material spreader across the build volume. The spreader cooler is in thermal conductive contact with the build material spreader. The spreader cooler has a second fluid conduit extending along the length. The cooling fluid supply directs cooling fluid in a first direction through the first fluid conduit and in a second direction, opposite the first direction, through the second fluid conduit.

A system is disclosed for additively manufacturing a composite structure. The system may include a print head configured to discharge a continuous reinforcement that is at least partially coated in a matrix, and a compactor configured to compact the continuous reinforcement and the matrix. The system may also include a cure enhancer configured to direct a path of cure energy toward the matrix after discharge, wherein the path of cure energy passes through at least a portion of the compactor.

A system is disclosed for additively manufacturing a composite structure. The system may include a print head configured to discharge a continuous reinforcement that is at least partially coated in a matrix, and a compactor configured to compact the continuous reinforcement and the matrix. The system may also include a cure enhancer configured to direct a path of cure energy toward the matrix after discharge, wherein the path of cure energy passes through at least a portion of the compactor.

A system for building a three dimensional green compact comprising a printing station configured to print a mask pattern on a building surface, wherein the mask pattern is formed of solidifiable material; a powder delivery station configured to apply a layer of powder material on the mask pattern; a die compaction station for compacting the layer formed by the powder material and the mask pattern; and a stage configured to repeatedly advance a building tray to each of the printing station, the powder delivery station and the die compaction station to build a plurality of layers that together form the three dimensional green compact.

A system for building a three dimensional green compact comprising a printing station configured to print a mask pattern on a building surface, wherein the mask pattern is formed of solidifiable material; a powder delivery station configured to apply a layer of powder material on the mask pattern; a die compaction station for compacting the layer formed by the powder material and the mask pattern; and a stage configured to repeatedly advance a building tray to each of the printing station, the powder delivery station and the die compaction station to build a plurality of layers that together form the three dimensional green compact.

There is provided a method of fabricating a three-dimensional object. The method includes supplying, flattening, and collecting. The supplying supplies, with a powder supplier, powder to a fabrication chamber. The fabrication chamber includes a fabrication stage to store powder and an outer edge portion outside the fabrication stage, the outer edge portion having one bottom surface. The flattening flattens, with a flattener, the powder supplied by the supplying. The collecting collects, with a powder collector, the powder having overflowed from the fabrication stage to the outer edge portion by the flattening into the fabrication stage.

There is provided a method of fabricating a three-dimensional object. The method includes supplying, flattening, and collecting. The supplying supplies, with a powder supplier, powder to a fabrication chamber. The fabrication chamber includes a fabrication stage to store powder and an outer edge portion outside the fabrication stage, the outer edge portion having one bottom surface. The flattening flattens, with a flattener, the powder supplied by the supplying. The collecting collects, with a powder collector, the powder having overflowed from the fabrication stage to the outer edge portion by the flattening into the fabrication stage.

At a print temperature, a layer (having a predetermined height) of metal build material particles is formed. Also at the print temperature, a fluid containing metal nanoparticles is selectively applied to at least a portion of the layer, and at a fluid loading that wets the portion through the predetermined height without saturating the portion. The metal nanoparticles are exposed to a sintering temperature that is higher than the print temperature and at least 500° below a melting point of the metal build material particles using a predetermined number of heating events taking place at a predetermined speed or for a predetermined time, and separated by a predetermined delay time, to bind the metal build material particles together to form a bound layer. A build material surface is cooled to or below the print temperature. The forming, selectively applying, exposing, and cooling are repeated to form a part precursor.

A system for compacting layers of metal powder, including: a layer of metal powder at a first voltage; and a conductive object above the layer of metal powder, the conductive object at a second voltage, wherein a voltage differential between the layer of metal powder and the conductive object is sufficient to attract particles from the layer of metal powder to the conductive object, change the voltage on the particles, and redeposit the particles in the layer of metal powder.