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.

The present invention has solved the problems of conventional molding materials, and provides a hydraulic composition for additive manufacturing devices having high strength development, particularly high early strength development, and less generation of gas defect and graphite spheroidization defect. Specifically, the hydraulic composition for additive manufacturing devices of the present invention at least contains calcium aluminate. It is preferable that the hydraulic composition contain 0.5-10 parts by mass of gypsum with respect to 100 parts by mass of the calcium aluminate.

Methods for making carbon-fiber reinforced geopolymer composites are provided. The methods produce metakaolin-based geopolymer composites in which multiwalled carbon nanotubes and/or carbon nanofibers are well dispersed in an metakaolin-based geopolymer matrix. The mixing protocols of the methods used to produce carbon-fiber reinforced geopolymer composites produce composites with reduced porosity, high elastic moduli, high strength, and/or high fracture toughness.

The invention relates to a method for layer-by-layer deposition of concrete by providing extrudable concrete. A first flow comprising a binder material and water and a second flow comprising a carrier material, an additional component and water are mixed in a static mixer to form a third flow of extrudable concrete. The material of the second flow has a shorter initial setting time than the material of the first flow. The first flow has a first viscosity V1 and the second flow has a second viscosity V2 so that the ratio V1/V2 ranges between 1/40 and 40. The third flow has a viscosity larger than the viscosity of the first flow and the second flow and a yield stress larger than the yield stress of the first flow and the second flow. The material of the third flow has an initial setting time shorter than initial setting time of the first flow.

The invention further relates to a system to extrude concrete, in particular for layer-by-layer deposition of concrete.

The use of bacteria-based binders to bind and strengthen 3D printed compositions; bio-plastic 3D printing materials comprised of combinations of particles of organic substrates such as coffee, pistachio shells and coconut shells, as well as sand (and combinations of one or more of the foregoing); processes for creating scent-free bio-plastic 3D printing material and products from such particles; the application of a copper finish, chrome finish and powder finish to bio-plastics made from such particles; and products and fixtures, such as sinks, toilets, faucets, coffee mug molds, lighting fixtures, and coffee cups, comprising non-flammable bio-plastic created by a process of 3D printing from such particles. Processes for imparting color or structure or surface texture to these and binding and strengthening them using enzyme-secreting bacteria.

The present invention relates to the use of a formulation comprising a phosphocalcic cement and a physical and/or ovalent hydrogel of polysaccharides for 3D printing, more particularly for bone regeneration and/or bone repair. The present invention also relates to a kit for 3D printing of bone implants comprising a phosphocalcic cement and a physical and/or covalent hydrogel of polysaccharides as well as to a method to prepare a formulation for 3D printing comprising a step of mixing a phosphocalcic cement and a physical and/or covalent liquid hydrogel precursor of polysaccharides.

A geopolymeric ink formulation for direct 3D printing containing a geopolymeric formulation whose components are present in such proportions as to be subjected to a geopolymerization reaction and to provide, at the end of the reaction, a solid geopolymer and wherein the formulation, before and during at least a part of the geopolymerization reaction, wherein three-dimensional chemical bonds have not yet been formed, forms a reversible-gel, non-Newtonian, viscoelastic fluid. The formulation is extruded through a 3D printing tool equipped with nozzle into strands according to a geometry such as to create a three-dimensional structure on one or more layers. The extrusion preferably takes place within a hydrophobic liquid, such as oil.

The invention relates to a method for manufacturing a multicapillary packing for an exchange of material including the formation, by a 3D printing method, of a monolith having a porous mass through which a plurality of parallel channels passes, opening on an inlet face and an outlet face of the packing, the 3D printing method being chosen among: selective laser sintering, molten wire deposition, stereolithography, binder spraying and spraying of material, the porous mass being suitable for allowing the diffusion of material to be exchanged between the channels.

Methods and systems for cementing a wellbore are described. The methods include forming a slurry including a cement-based matrix, water, a polymer-based additive, and a rheology modifying agent; mixing the slurry to form a printing ink; introducing the slurry and a printer into a wellbore; and forming a cement-based composite structure in the wellbore by printing a plurality of layers using the printing ink.

A mixing-extruding head apparatus for a three-dimensional (3D) printer for building residential houses and other objects, which enables printing of right-angled corners, the apparatus comprising a container for mixing mortar, the container comprising a funnel (1), a two-part helix (6) inside the container for mixing the mortar for building said objects, wherein the two-part helix (6) is installed on a main axis (2) inside the funnel (1) and the helix (6) comprises an inner metal part (6a) and an outer rubber part (6b), and wherein the helix (6) has at least one thread (turn), and an exit nozzle (14). The bottom part of the exit nozzle (14) is on each of its sides equipped with one of four blades (17), which are controlled by a servo-pneumatic system with computer-controlled commands for building the objects, wherein each of the blades is connected to a piston moved by a pneumatic cylinder; wherein all four pneumatic cylinders are connected with four electromagnetic valves, which generate pneumatic signals.