To provide a binder composition for molding, by which a mold made of aggregate has an excellent resistance to moisture. The binder composition for molding contains a water-soluble binder and at least one kind of lithium salt that is selected from a group of lithium silicate, lithium oxide, lithium hydroxide, lithium carbonate, lithium bromide, lithium chloride, lithium nitrate, and lithium nitrite.

To provide a binder composition for molding, by which a mold made of aggregate has an excellent resistance to moisture. The binder composition for molding contains a water-soluble binder and at least one kind of lithium salt that is selected from a group of lithium silicate, lithium oxide, lithium hydroxide, lithium carbonate, lithium bromide, lithium chloride, lithium nitrate, and lithium nitrite.

The invention relates to a mold material mixture for producing casting molds for metal processing, a process for producing casting molds, casting molds which can be obtained by the process and their use. The production of the casting molds is carried out using a refractory base molding material and a binder based on water glass. A proportion of a particulate metal oxide selected from the group consisting of silicon dioxide, aluminium oxide, titanium oxide and zinc oxide is added to the binder, with particular preference being given to using synthetic amorphous silicon dioxide. The mold material mixture contains a surface-active material as further significant constituent. The addition of the surface-active material enables the flowability of the mold material mixture to be improved, which makes it possible to produce casting molds having a very complicated geometry.

Material system suitable for a 3D printing method or 3D printing method material system comprising or consisting of a particulate material, a printing liquid, and an ester activator as well as 3D printing processes that use such a material system and molding parts produced by means of such material systems and 3D printing processes.

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.

Compositions useful for foundry processes such as green sandcasting are discussed. The compositions may comprise ball clay, bentonite, and a carbonaceous material. The ball clay may comprise leonardite and/or causticized lignite, e.g., as a portion of the natural ball clay deposit. The composition may further comprise sand, such that the resulting mixture may be formed into a green sand mold for use in casting molded articles. Incorporation of ball clay materials in the compositions may help to improve the quality of the casted article.

The invention relates to a binder system for production of a slip, e.g., for a green casting core compact. The invention also relates to a component that has been produced by means of such a slip. The invention may be employable for relatively inexpensive production of complex metal blades in all kinds of gas turbines and propulsion turbines. According to an embodiment, the invention provides a novel binder system that combines short gel times at room temperature without solvent while retaining a high glass transition of 55 to 60 C. with shortened hardening periods.

The invention relates to a binder system for production of a slip, e.g., for a green casting core compact. The invention also relates to a component that has been produced by means of such a slip. The invention may be employable for relatively inexpensive production of complex metal blades in all kinds of gas turbines and propulsion turbines. According to an embodiment, the invention provides a novel binder system that combines short gel times at room temperature without solvent while retaining a high glass transition of 55 to 60 C. with shortened hardening periods.

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 method of forming a dry molding sand additive may include recovering a non-sand fraction from a foundry waste material and adding the non-sand fraction to a dry molding sand additive formulation to form a dry molding sand additive. Adding the non-sand fraction to the dry molding sand additive formulation may reduce the amount of fresh clay and carbon to produce the dry molding sand additive. A method of forming a molding sand additive may include recovering a waste molding sand additive composition having a clay or carbon content differing from a desired clay and carbon content, recycling the waste molding sand additive as a raw material in production of a fresh molding sand additive, and adjusting the amount of fresh clay or carbon added during production of the fresh molding sand additive to achieve the desired clay and carbon content.