Surface retarder coating compositions of the invention are based on the use of at least one non-Ordinary Portland Cement (non-OPC) binder and at least one OPC set retarder agent, which are provided in powder form that can be mixed with water at the construction site. The coating is applied onto the surface of a mould or formwork using roller or spray equipment, and concrete can then be cast within 30-60 minutes against the coating. The OPC set-retarding agent operates to retard setting of the concrete so that it can be de-moulded the next day and its surface can be removed using a high pressure water spray to reveal aggregate embedded beneath the removed surface.

A self-bonding refractory powder product for use in making a slurry for investment casting molds comprising a coarse refractory powder; a Nano-sized powder; and an organic polymer powder, wherein it does not require aqueous colloidal silica to produce slurries used to build investment casting molds. The Nano-sized powder comprises fumed alumina, boehmite, fumed silica, or fumed titanium oxide or combinations thereof. The coarse refractory powder comprises milled zircon, tabular alumina or fused alumina, fused silica, alumino-silicate, zirconia, and yttria or combinations thereof. The organic polymer powder comprises a cellulose-based material.

Provided herein is a system, apparatus, and method for producing refractory products, and more particularly, to producing heated refractories, passive refractories, transition plates, moldable refractories, and accessories such as heated spouts, heated pins, thimbles, and dams. A heated refractory channel as disclosed herein may include a working surface to contain molten metal within the channel; a core adjacent to the working surface; one or more heating elements disposed within the core; and insulation, where the core is disposed between the working surface and the insulation. The one or more heating elements may be molded into the core. The heating elements may be electrical resistance heating elements.

Compositions useful for foundry processes such as green sand casting are discussed. The compositions may comprise an aggregate, at least one inorganic binding agent, and at least one high aspect ratio silicate. For example, the composition may comprise sand, one or more clay materials serving as a binding agent, and a high aspect ratio silicate chosen from mica, talc, or a combination thereof. The composition may be formed into a green sand mold for use in casting molded articles. Incorporation of the high aspect ratio silicate may help to improve the quality of the casted article.

A description is given of the use of an additive mixture (A) for combination with a solution or dispersion (B) comprising waterglass, for producing a moulding material mixture for producing articles from the group consisting of foundry moulds and foundry cores; a multi-component binder system comprising (A) an additive mixture and (B) a solution or dispersion comprising waterglass; a moulding material mixture comprising a mould base material (C) and also components (A) and (B) of such a multi-component binder system; a method for producing an article from the group consisting of foundry moulds and foundry cores; articles from the group consisting of foundry moulds and foundry cores; and the use of such an article for metal casting, preferably for light metal casting, more particularly for aluminium casting.

A method of producing an additively manufactured casting mould for the production of components using the cold casting process or lamination process, comprising the steps of a) determining a three-dimensional structure of the casting mould, b) providing a mixture, the mixture comprising a binding agent and an aggregate, c) providing a printing fluid comprising an aqueous solution of magnesium chloride or magnesium sulfate, d) applying a layer of the mixture to a support, e) applying the printing fluid only to those parts of the mixture which are supposed to constitute a part of the casting mould, f) applying a further layer of the mixture to the previous layer of the mixture, g) applying the printing fluid only to those parts of the mixture which are supposed to constitute a part of the casting mould, h) repeating steps f) and g) until the desired shape of the casting mould is achieved, i) allowing those parts of the mixture to set which have been mixed with the aqueous solution of magnesium chloride or magnesium sulfate, j) removing the mixture which has not been mixed with an aqueous solution, and coating with a formwork skin at least those parts of the casting mould which come into contact with the material of the cold-casting lamination process.

A method of forming a lightweight concrete block and the resulting structure. Calcium sulfoaluminate (CSA) cement and specialized grout maybe added to an amount of water in a mixer. The CSA cement, specialized grout, and water may be blended to a smooth consistency. Lightweight aggregates (LWA) maybe added to form a mixture. The mixture may be poured into a mold, allowed the mixture to cure, and removed from the mold to form the lightweight concrete block. The lightweight concrete block may have a first side and a second side joined by a plurality of interposing walls, the interposing walls defining one or more inner cavities and one or more outer cavities. The lightweight concrete block may have features that allow for the insertion of fiberglass rebar to aide in stacking and filling to form a wall.

A method for producing a dental restoration (D) by CAD casting is described, said method comprising the steps of a) recording three-dimensional, digital data of the dentition or of a part of the dentition of a patient, b) creating a virtual dental restoration (VD) using the recorded three-dimensional, digital data, wherein the virtual dental restoration (VD) is expanded in relation to the dental restoration (D) to be produced, c) preparing a model (M) using the created virtual dental restoration, such that the model (M) is expanded in relation to the dental restoration (D) to be produced, d) embedding the model (M) in an embedding compound (EM), e) hardening the embedding compound (EM) and removing the model (M), such that a casting mold is obtained, f) filling the casting mold, preferably by pouring, with a casting material (GM) and cooling the casting material (GM), such that the dental restoration (D) is obtained, and optionally the further steps of g) working the dental restoration (D), and h) veneering the dental restoration (D). A novel embedding compound (EM) is also described that has no expansion or at least is only a slight expansion on setting.

The invention relates to a pulverulent composition comprising, based on the overall mass of the composition, A) at least 20 wt % of a calcium sulfate-based binder and B) 0.01 to 4 wt % of at least one copolymer obtainable by polymerizing a mixture of monomers comprising (I) at least one ethylenically unsaturated monomer which comprises at least one radical from the series carboxylic acid, carboxylic salt, carboxylic ester, carboxylic amide, carboxylic anhydride, and carboxylic imide and (II) at least one ethylenically unsaturated monomer having a polyalkylene oxide radical, the pulverulent composition being producible by a method in which a powder component comprising a calcium sulfate-based binder is contacted with a liquid hydrous component comprising less than 30 wt % of an organic solvent, comprising B), the liquid hydrous component being used in an amount of less than 20 wt %, based on the overall mass of the pulverulent composition, and the pulverulent composition comprising no hydraulic binder. A binder composition comprising an inventive pulverulent composition is also disclosed.

A method of forming a lightweight polished concrete and the resulting composition. Calcium sulfoaluminate (CSA) cement and specialized grout may be added to an amount of water in a mixer. The CSA cement, specialized grout, and water may be blended to a smooth consistency. Lightweight aggregates (LWA) may be added to the blended CSA cement, specialized grout, and water to form a mixture. The mixture may be poured over a fiberglass rebar, vibrated, screeded, and allowed to set. The set mixture may be smoothed with float blades. The smoothed mixture may be hardened with metal blades, such that the hardened mixture becomes reflective. A concrete densifier may be applied to the hardened mixture to form the lightweight polished concrete. Optionally, one or more saw cuts may be formed in the lightweight polished concrete and a coating to may be applied to fill the one or more saw cuts.