The present invention relates to the use of closed-pore microspheres of expanded perlite as a filler for producing moldings for the foundry industry, to a composition for producing moldings for the foundry industry, comprising closed-pore microspheres of expanded perlite as a filler, and a binder, the binder being selected from the group consisting of water glass, phenol-formaldehyde resins, two-component systems comprising as reactants a polyisocyanate and a polyol component containing free hydroxyl groups (OH groups), and starch, and also to moldings for the foundry industry and to a process for producing a molding for the foundry industry.

A castable refractory material for use in the manufacture of refractory products including fused silica, ceramic fiber, microsilica and a bonding material comprising colloidal silica.

A method for casting an internal feature within an object is provided. An internal mold is formed from a mold powder, comprising a base powder and an acid powder mixed into the base powder. A molten material is cast around the internal mold. The molten material is solidified. The internal mold is reacted with water, wherein the reacting causes the acid powder to neutralize the base powder.

A method for casting an internal feature within an object is provided. An internal mold is formed from a mold powder, comprising a base powder and an acid powder mixed into the base powder. A molten material is cast around the internal mold. The molten material is solidified. The internal mold is reacted with water, wherein the reacting causes the acid powder to neutralize the base powder.

The subject matter of the present invention is a binder system containing blocked tertiary amines or amidines as co-catalysts for a polyurethane cold-box application. It also relates to the molding material mixtures produced using such a binder system further comprising volatile tertiary amines, a method for producing the molding material mixtures, and the cores and molds made from the molding material mixtures according to the cold-box process.

There is provided a binder for molding a casting mold, which contains water glass and aluminum silicate obtained by carrying out dissolution in the water glass, where the binder for molding a casting mold contains 2 to 15 parts by mass of the aluminum silicate with respect to 100 parts by mass of a solid content of the water glass.

A binder composition for making foundry molds, comprising an acid-hardening resin, one or more 5-position-substituted-furfural compounds selected from the group consisting of 5-hydroxymethylfurfural and 5-acetoxymethylfurfural, and one or more compounds selected from the group consisting of urea and derivatives of urea, wherein the content of the 5-position-substituted-furfural compound(s) by percentage is from 1 to 60% by weight of the binder composition. The content of the compound(s) by percentage selected from the group consisting of urea and derivatives of urea is preferably from 0.3 to 10% by weight of the binder composition.

A method of reusing core sand includes: crushing a core used for casting into granules; heating the granules at a temperature of 300 C. to 550 C.; causing the heated granules to collide against each other such that water glass used as a binder detaches from the core sand; and blowing air into a mixture of the water glass and the core sand, which are detached from each other, such that the core sand is separated and collected from the mixture due to a difference in specific gravity between the water glass and the core sand.

A green sand mold for producing a cast steel article, which is formed by casting sand comprising sand, a binder, and 3 parts or less by mass of a carbonaceous component per 100 parts by mass of sand, and provided with a coating layer of a thermosetting resin formed at least on a recess including a cavity for forming the cast steel article, the coating layer having average hardness (measured by a self-hardening hardness meter) of 50-95 and a thickness of 0.5-2.5 mm.

The disclosure relates generally to mold compositions and methods of molding and the articles so molded. More specifically, the disclosure relates to mold compositions, intrinsic facecoat compositions, and methods for casting titanium-containing articles, and the titanium-containing articles so molded, where the mold comprises calcium hexaluminate.