The present invention relates to a suspension comprising 50-95% by weight of the total suspension (w/w) of at least one metallic material and/or ceramic material and/or polymeric material and/or solid carbon containing material; and at least 5% by weight of the total suspension of one or more fatty acids or derivatives thereof. In addition, the invention relates to uses of such suspension in 3D printing processes.

A powder spreading apparatus includes a hopper having a first end, a second end opposite from the first end, a front wall, a rear wall opposite from the front wall, and a floor. The front wall, the rear wall, the first end, the second end, and the floor define an interior. An impeller is disposed within the interior of the hopper. The impeller includes a plurality of circumferentially spaced flutes and is configured to rotate about an impeller axis that extends from the first end of the hopper to the second end of the hopper to deposit powder onto a print area. A spreader rod is coupled to the hopper and extends along a spreader rod axis parallel to the impeller axis. The spreader rod is configured to rotate about the spreader rod axis to smooth the powder as it is deposited onto the print area.

The invention relates to a binder, which contains water glass and further a phosphate or a borate or both. The invention further relates to a method for constructing molds and cores layer by layer, the molds and cores comprising a construction material mixture, which at least comprises a refractory molding base material, and the binder. In order to produce the molds and cores layer by layer in 3-D printing, the refractory molding base material is applied layer by layer and is selectively printed with the binder layer by layer, and consequently a body corresponding to the molds or cores is constructed and the molds or cores are released after the unbonded construction material mixture has been removed.

The invention relates to a method and an apparatus for producing three-dimensional models by layering technology, and a recoater with a vacuum closure.

An irradiation device for additively manufacturing three-dimensional objects may include a beam generation device that includes a plurality of laser diode arrays. Respective ones of the plurality of laser diode arrays may include a plurality of diode emitters respectively configured to emit an energy beam. The plurality of laser diode arrays may be longitudinally offset relative to one another, and the plurality of laser diode arrays may be laterally offset relative to one another.

An irradiation device for additively manufacturing three-dimensional objects may include a beam generation device configured to generate an energy beam, an optical modulator including a micromirror array disposed downstream from the beam generation device, and a focusing lens assembly disposed downstream from the optical modulator. The micromirror array may include a plurality of micromirror elements configured to reflect a corresponding plurality of beam segment of the energy beam along a beam path incident upon the focusing lens assembly. The focusing lens assembly may include one or more lenses configured to focus the plurality of beam segments such that for respective ones of a plurality of modulation groups including a subset of micromirror elements, a corresponding subset of beam segments are focused to at least partially overlap with one another at a combination zone corresponding to the respective modulation group.

A method is provided for casting a component. Accordingly, data indicative of at least one location of a unitary core-shell mold which is susceptible to a stress concentration is received. An additive manufacturing process is employed to form the unitary core-shell mold defining a casting cavity. The unitary core-shell mold includes a shell wall defining an outer component shape and a core wall positioned inward of the shell wall. The core wall defines an inner component shape. The core wall and/or the shell wall defines at least one reinforcement recess adjacent to the at least one location which is susceptible to the stress concentration. Following the forming of the unitary core-shell mold, at least one support member is positioned within the reinforcement recess in contact with the at least one location. With the support member in place, the component is cast within the casting cavity.

Stone slabs, and systems and methods of forming slabs, are described. Some example slabs include a first pattern defined by a first particulate mineral mix and a second pattern defined by a second particulate mineral mix different from the first particulate mineral mix. Locations of the first pattern have a first average thickness perpendicular to the slab width and the slab length, and locations of the second pattern have a second average thickness perpendicular to the slab width and the slab length that is different from the first average thickness.

An apparatus for producing a three-dimensional work piece is provided. The apparatus comprises an irradiation unit comprising at least one scanning unit configured to scan a radiation beam over an uppermost layer of raw material powder to predetermined sites of the uppermost layer of the raw material powder in order to solidify the raw material powder at the predetermined sites. An axis corresponding to the radiation beam when it impinges on the uppermost layer of raw material powder at an angle of 90° is defined as a central axis for the scanning unit. The apparatus further comprises a control unit configured to receive work piece data indicative of at least one layer of the three-dimensional work piece to be produced, and assign at least a part of a contour of the layer of the three-dimensional work piece to the at least one scanning unit. According to a first aspect, the control unit is configured to generate control data for controlling the irradiation unit, the control data defining a scan strategy of the radiation beam such that for more than 50% of a predefined length, the radiation beam moves away from the central axis, the predefined length being defined as a length the radiation beam moves along the contour assigned to the at least one scanning unit, excluding sections concentric with regard to the central axis. Further, corresponding methods and computer program products are provided.

A 3D printing system for construction includes a 3D printing assembly having a pair of tower assemblies, and a pair of rail assemblies. The pair of tower assemblies are movably disposed on the pair of rail assemblies. Each of the pair of rail assemblies defines a longitudinal axis and the pair of tower assemblies are configured to move on the pair of rail assemblies in a direction along the longitudinal axis. Each of the rail assemblies includes a plurality of rail parts. Each of the rail parts includes at least one track extending along the longitudinal axis, an aligning protrusion at a first end portion thereof, and an aligning groove at a second end portion thereof. The aligning groove is configured to accept the aligning protrusion of an adjacent rail part.