A structure for manufacturing castings, containing an inorganic fiber, a layered clay mineral, and an inorganic particle other than the layered clay mineral and having an organic content of 5 mass % or lower or having a mass loss of 5 mass % or lower when heated at 1000° C. for 30 minutes. The inorganic particle preferably contains one or more selected from obsidian, graphite, and mullite. The inorganic fiber preferably contains carbon fiber. The inorganic fiber preferably has an average length of 0.5 to 15 mm. The layered clay mineral preferably contains one or more selected from bentonite and montmorillonite.

The present invention relates to a resin composition that comprises an acetoacetate ester compound with at least two acetoacetate ester functional groups, an acrylate compound with at least two acrylate functional groups, and a tertiary amine curing catalyst. This resin composition acts as an isocyanate-free binder that is less toxic to the environment. The invention further discloses a method for preparation fiber reinforced parts comprising fibers and said resin composition as well as a method for the preparation of foundry molds for the casting industry, which is based on said binder.

The present invention provides a curing agent for casting a water glass, including an ester and an amorphous silicon dioxide obtained by a thermal decomposition of ZrSiO.sub.4; and the curing agent for casting the water glass does not contain water. According to the present invention, the curing agent for casting the water glass has a strong adhesion-enhancing effect and a long shelf life, and is easy to use.

A casting green sand mold comprising at least a pair of green sand mold parts each having a cavity portion, which are stacked with their cavity portions aligned to form a metal-melt-receiving cavity; each of the green sand mold parts being formed by casting sand containing a binder and water; a hardening-resin-based coating layer being formed on at least the cavity portion of each green sand mold part; the coating layer having gas-permeable pores having sufficient permeability to permit a gas generated by pouring a metal melt to escape; and a water content in a surface layer including the coating layer in a range from the cavity surface to the depth of 5 mm being smaller than that in the inner portion of the green sand mold.

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.

What are described is a process for producing casting molds, cores and mold base materials regenerated therefrom, a mixture for combination with a solution or dispersion comprising waterglass for production of casting molds and/or cores, a molding material mixture, a mold base material mixture, and a casting mold or a core. What is also described is the corresponding use of an amount of particulate sheet silicates having a d.sub.90 of less than 45 μm or a corresponding mixture as additive for production of a molding material mixture comprising waterglass and particulate amorphous silicon dioxide, which is cured by chemical reaction of constituents of the molding material mixture with one another, in the production of a casting mold or a core, to facilitate the breakdown and/or to increase the regeneratability of the casting mold or core.

The present disclosure includes binder systems for making foundry articles. The binder systems may comprise a humic substance-containing component that comprise lignite, an isocyanate component, and a catalyst component. The binder systems may be mixed with an aggregate (e.g., sand) for making foundry articles such as molds and cores. Also disclosed herein are methods of making foundry articles using the binder systems.

What are described is a process for producing casting molds, cores and mold base materials regenerated therefrom, a mixture for combination with a solution or dispersion comprising waterglass for production of casting molds and/or cores, a molding material mixture, a mold base material mixture, and a casting mold or a core. What is also described is the corresponding use of an amount of particulate sheet silicates having a d.sub.90 of less than 45 μm or a corresponding mixture as additive for production of a molding material mixture comprising waterglass and particulate amorphous silicon dioxide, which is cured by chemical reaction of constituents of the molding material mixture with one another, in the production of a casting mold or a core, to facilitate the breakdown and/or to increase the regeneratability of the casting mold or core.

A casting green sand mold comprising at least a pair of green sand mold parts each having a cavity portion, which are stacked with their cavity portions aligned to form a metal-melt-receiving cavity; each of the green sand mold parts being formed by casting sand containing a binder and water; a hardening-resin-based coating layer being formed on at least the cavity portion of each green sand mold part; the coating layer having gas-permeable pores having sufficient permeability to permit a gas generated by pouring a metal melt to escape; and a water content in a surface layer including the coating layer in a range from the cavity surface to the depth of 5 mm being smaller than that in the inner portion of the green sand mold.

The present invention relates to nanoparticle based sand conditioner composition and a method of synthesizing the same. The composition has the raw material compound RM 1, RM 2, RM 3 and RM 4. The RM1 has carbonaceous material, hydrocarbons, ultrafine metal/metal oxide and ceramic oxide nanoparticles and metallic wires. The RM 2 has natural carbon source. The RM 3 comprises synthetic/non-renewable carbon source. The RM 4 has hydrocarbons. The method of synthesizing nanoparticle based sand conditioner comprises mixing RM 2 and RM 4 in a mixer for 10 minutes for coating RM 2 with RM 4 to obtain an intermediate product. The RM 1 and RM 3 are added to an intermediate product in a mixer and mixed for 10 minutes to get a uniform/homogeneous mixture which is cooled to obtain a sand conditioner composition impregnated with nanoparticles into carbon.