A concrete construction (100) made by 3D concrete printing that contains: two or more layers (102, 106) of cementitious material extruded one above the other, and at least one elongated steel element (104, 108) reinforcing at least one of the two or more layers. The elongated steel element (104, 108) is provided with a first crimp. Due to the crimp, a good anchorage in concrete is obtained and the anchorage force is predictable, since the standard deviation of the anchorage force is very small. The elongated steel element can be a single steel wire with a diameter D, the amplitude of the crimp ranges from 1.05×D to 5.0×D. The elongated steel element can also be a steel with steel filaments having a maximum diameter d. The amplitude of the crimp ranges from 1.05×d to 5.0×d.

An interlayer pre-cooling apparatus for a sand mold freezing printing includes a sand paving apparatus. The sand paving apparatus is located above a negative-pressure low-temperature forming chamber, and the sand paving apparatus includes several independent sand paving grooves, a hollow sand paving roller, a cooling chamber, a sand scraping plate, and an openable and closable baffle. The openable and closable baffle is rotationally arranged at a discharge port of each sand paving apparatus, and the openable and closable baffle is used for paving low temperature premixed sand on demand. The premixed molding sand is further cooled during the process of scraping and compacting low-temperature molding sand. When the apparatus is adopted for sand mold freezing 3D printing, the low temperature of the premixed molding sand is precisely controllable, which has great significance for realizing interlayer pre-cooling of the sand mold freezing printing.

Compositions comprising preceramic resins and fumed alumina are described. The compositions can also include fillers, such as silicon carbide whiskers or zirconium diboride particles. The compositions can be used as three-dimensional printable inks for preparing ceramic composites, e.g., composites having complex geometry. Inclusion of fumed alumina as a rheology modifier in the composition can provide improved printing properties for the inks compared to preceramic resin inks that do not include fumed alumina.

A composite precursor powder, including one or more metals or metalloids, and one or more oxides, wherein a molar ratio of the one or more metals or metalloids to the one or more oxides is from about 1:0.01 to about 1:4, and wherein the molar ratio of the one or more metals or metalloids to the one or more oxides is configured according to a desired volumetric change of the composite precursor powder when converted to a non-oxide ceramic.

A method for producing an article containing silicon carbide as the main constituent includes a plurality of sets of steps of forming a layer of a raw material powder and irradiating the layer with laser light according to three-dimensional model data. The low material powder is a mixture of silicon carbide powder, metallic silicon powder, and carbon powder. The laser light used in the step of irradiation with laser light has a spatial laser power density of 11 J/mm.sup.3 to 50 J/mm.sup.3.

Provided is a three-dimensional object formation method for forming a three-dimensional object by at least repeating: forming a powder material layer using a powder material for three-dimensional object formation containing a base material coated with an organic material; and hardening a predetermined region of the powder material layer by delivering a hardening liquid to the powder material layer formed in the formation of a powder material layer, where the hardening liquid contains a cross-linking agent cross-linkable with the organic material.

An example device for building stationary structures on a work surface includes a scaffold, which is arranged around the work surface. In the example, a working head is provided, which, with the help of multiple control cables is held on the scaffold and arranged above the work surface, upper control cables are provided, which run above the working head from the scaffold, lower control cables are provided, which run below the working head from the scaffold, all control cables can be extended out of the scaffold and retracted to the scaffold, in order to change a position of the working head, and a control unit is provided, which is connected with actuators for the extending and retracting of the control cables, and is configured to actuate these actuators to change the position of the working head.

The disclosure provides methods and systems for measuring a base element of a construction cylinder arrangement in machines for the additive manufacture of 3D objects using a high-energy beam, wherein a measurement pattern is produced from laser light that illuminates the base element, and sites of incidence of the laser light are monitored and evaluated with a camera to produce measuring data about the base element, e.g., position information, orientation information, and/or information about the shape of the surface of the base element. The measurement patterns are produced by deflecting measuring laser beams by an optical scanner system towards the base element, and the camera is arranged laterally offset from the deflected laser beams. The new methods and systems enable measuring base elements in a simple and flexible manner, and require only a small amount of space in the processing chamber.

A method for manufacturing an engineered stone, the method including: providing a mixture comprising at least a stone or stone like material and a binder; compacting the mixture; curing the binder; and printing on at least a top surface of the engineered stone.

An electrostatic chuck for electrostatically attracting a substrate includes: a chuck body formed of first ceramic particles and having a substrate-facing surface facing the substrate attracted to the electrostatic chuck; and a plurality of convex portions formed on the substrate-facing surface of the chuck body, wherein each of the plurality of convex portions excluding at least a tip-side layer is formed of second ceramic particles having a major axis diameter of 20 μm or more and 2,000 μm or less and has a porosity of 0.1% or more and 1.0% or less.