An investment mold includes a mold cavity and a refractory investment wall that bounds at least a portion of the mold cavity. At least a portion of the refractory investment wall includes a plurality of fugitive beads. The fugitive beads can be sacrificed to provide voids that control the strength of the refractory investment wall such that the wall fractures at the voids during investment casting to alleviate stress on a solidified metal cast in the mold cavity.

An investment mold includes a mold cavity and a refractory investment wall that bounds at least a portion of the mold cavity. At least a portion of the refractory investment wall includes a plurality of fugitive beads. The fugitive beads can be sacrificed to provide voids that control the strength of the refractory investment wall such that the wall fractures at the voids during investment casting to alleviate stress on a solidified metal cast in the mold cavity.

Provided herein are a saltcore for casting with aluminum and a manufacturing method thereof, and more particularly, a saltcore and a manufacturing method thereof capable of reducing shrinkage while satisfying strength during die-casting by including at least one cation of K.sup.+, Na.sup.+ and Mg.sup.2+ and at least one anion of Cl.sup.? and C0.sub.3.sup.2?, wherein a saltcore for casting with aluminum may include at least one cation of K.sup.+, Na.sup.+ and Mg.sup.2+ and at least one anion of Cl.sup.? and C0.sub.3.sup.2?.

Provided herein are a saltcore for casting with aluminum and a manufacturing method thereof, and more particularly, a saltcore and a manufacturing method thereof capable of reducing shrinkage while satisfying strength during die-casting by including at least one cation of K.sup.+, Na.sup.+ and Mg.sup.2+ and at least one anion of Cl.sup.? and C0.sub.3.sup.2?, wherein a saltcore for casting with aluminum may include at least one cation of K.sup.+, Na.sup.+ and Mg.sup.2+ and at least one anion of Cl.sup.? and C0.sub.3.sup.2?.

A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.

A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.

Feeders for use in the foundry industry comprising (a) rice husk ash containing, based on the total amount of the constituents detectable in the rice husk ash by quantitative phase analysis by means of x-ray diffractometry (i) crystalline modifications of silicon dioxide, (ii) monoclinic feldspar and (iii) amorphous silicon dioxide, a total content of at least 70 wt. %, preferably more than 75 wt. % of (i) crystalline modifications of silicon dioxide and (ii) monoclinic feldspar, wherein, based on the total weight of the shapeable composition of the feeder, the amount of this rice husk ash is in the range of from 5 to 50 wt. %, preferably 5 to 25 wt. %, (b) cured binder, (c) optionally fiber material, (d) optionally one or more further fillers, and (e) optionally an oxidizable metal and an oxidizing agent for the oxidizable metal are described.

Feeders for use in the foundry industry comprising (a) rice husk ash containing, based on the total amount of the constituents detectable in the rice husk ash by quantitative phase analysis by means of x-ray diffractometry (i) crystalline modifications of silicon dioxide, (ii) monoclinic feldspar and (iii) amorphous silicon dioxide, a total content of at least 70 wt. %, preferably more than 75 wt. % of (i) crystalline modifications of silicon dioxide and (ii) monoclinic feldspar, wherein, based on the total weight of the shapeable composition of the feeder, the amount of this rice husk ash is in the range of from 5 to 50 wt. %, preferably 5 to 25 wt. %, (b) cured binder, (c) optionally fiber material, (d) optionally one or more further fillers, and (e) optionally an oxidizable metal and an oxidizing agent for the oxidizable metal are described.

Provided are slurry compositions and methods for producing investment casting molds. These compositions include a refractory material, a binder, a solvent, and a thixotropic agent comprising a polymer emulsion. Implementation of these slurry compositions enables a reduction in the number of backup layers in an investment casting shell, while retaining similar viscosity characteristics and similar or greater strength characteristics in the finished investment mold.

Provided are slurry compositions and methods for producing investment casting molds. These compositions include a refractory material, a binder, a solvent, and a thixotropic agent comprising a polymer emulsion. Implementation of these slurry compositions enables a reduction in the number of backup layers in an investment casting shell, while retaining similar viscosity characteristics and similar or greater strength characteristics in the finished investment mold.