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 composition for making cores and a process for metal casting, the composition comprising: a particulate refractory material; an inorganic binder comprising at least one alkali metal silicate; a pozzolanic additive; and a lustrous carbon former. The process includes forming a core from the composition and assembling a mould comprising the core and supplying molten metal.

The invention relates to molding material mixtures containing barium sulfate in combination with refractory basic molding materials and a waterglass-based binder system for producing casting molds and cores for the foundry industry in order to obtain cast pieces, in particular aluminum ones, which have an improved cast surface.

Provided is a granular material which generates no harmful gas at the time of pouring, reduces a gas defect as one of casting defects, and is readily reusable after pouring, in the manufacture of a three-dimensional laminated and shaped mold. This granular material is a granular material for use in a three-dimensional laminated and shaped mold manufacturing apparatus, and includes magnesium sulfate. The amount of magnesium sulfate included in the granular material is 1 to 10 pts.Math.mass with respect to 100 pts.Math.mass of the granular material. The amount of water included in the granular material is 0.1 mass % or less except for crystallization water of magnesium sulfate.

Provided is a granular material which generates no harmful gas at the time of pouring, reduces a gas defect as one of casting defects, and is readily reusable after pouring, in the manufacture of a three-dimensional laminated and shaped mold. This granular material is a granular material for use in a three-dimensional laminated and shaped mold manufacturing apparatus, and includes magnesium sulfate. The amount of magnesium sulfate included in the granular material is 1 to 10 pts.Math.mass with respect to 100 pts.Math.mass of the granular material. The amount of water included in the granular material is 0.1 mass % or less except for crystallization water of magnesium sulfate.

The invention relates to a molding mixture for producing casting molds for metalworking, a process for producing casting molds, casting molds obtained by the process and also their use. To produce the casting molds, a refractory mold raw material and a binder based on water glass are used. A proportion of a particulate metal oxide selected from the group consisting of silicon dioxide, aluminum oxide, titanium oxide and zinc oxide is added to the binder, particular preference being given to using synthetic amorphous silicon dioxide. The molding mixture contains a phosphate as essential constituent. The use of phosphate can improve the mechanical strength of casting molds at high thermal load.

The invention relates to molding material mixtures containing a molding base material, water glass, amorphous silicon dioxide and an oxidic boron compound, and the production of molds and cores, in particular for metal casting.

The additive composition of the present invention is one blended in a sand composition which is subjected to foaming to mold a sand mold, and includes (A) an alkylsulfonate metal salt having an alkyl group with 9 to 22 carbon atoms. The additive composition may further include at least one component selected from a group consisting of (B) an alkylsulfate metal salt, (C) a polyoxyalkylene alkyl ether sulfate metal salt, and (D) an alkylbenzene sulfonate metal salt.

The additive composition of the present invention is one blended in a sand composition which is subjected to foaming to mold a sand mold, and includes (A) an alkylsulfonate metal salt having an alkyl group with 9 to 22 carbon atoms. The additive composition may further include at least one component selected from a group consisting of (B) an alkylsulfate metal salt, (C) a polyoxyalkylene alkyl ether sulfate metal salt, and (D) an alkylbenzene sulfonate metal salt.

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.