Abstract: A system for producing cast components from molten metal. One form of the present invention includes a system for the precision pouring of molten metal within a casting mold.

Abstract: A process for the assembly of wax trees in which a wax runner is placed in a flat position and a wax pattern is located adjacent the wax runner. Both the wax runner pattern and the wax runner are heated and then are placed in contact with one another where heated. Then the wax pattern and the wax runner are separated slightly to form a fillet weld between the wax pattern and the wax runner. An apparatus is also provided which, by robotics, brings a multiplicity of wax patterns to a wax runner and which automatically heats both the wax patterns and the wax runner before simultaneously pressing both the wax pattern and the wax runner together. Once a wax tree assembly is completed a new wax runner replaces the wax runner that has been formed into a wax tree and additional wax runners are affixed in the same manner.

Abstract: In the lost foam casting of aluminum, coating a fugitive pattern with a refractory coating containing a thermally stable, water-insoluble, acid-gasifiable (e.g. CaCO3) compound, and contacting the casting, with the coating thereon, with an acid to dissociate and gasify the compound and rupture the coating. Preferably, any thermal degradation products from the pattern residing in the coating are neutralized to promote wetting of the coating.

Abstract: A peripheral flange formed on a differential case for mounting a ring gear and the peripheral flange is provided with a plurality of cast-in bolt holes for bolting up the ring gear to the differential case using the lost foam casting process for making the differential case. A method of making a gear case eliminates the process of machining of the bolt holes in the differential case casting, thus reducing cost of manufacturing the differential case.

Abstract: A sprue structure is specifically designed to facilitate the rapid filling of molded polystyrene patterns with molten metal. It comprises a down sprue and parallel columnar members that are connected to the down sprue. The flow of molten metal is initially downward through the first columnar member and then it reverses direction to flow upwardly through second and third columnar members so that the patterns to be cast receive molten metal as it travels upwardly through the second and third columnar members. This decreases the amount of pyrolyzation products that could otherwise flow through in-gates and into the patterns to be cast.

Abstract: An apparatus and method to delay the application of pressure on a molten metal front to equalize a pressure gradient present at the molten metal front during pressurized lost foam casting processes, or other pressurized casting processes. A pressure equalization member is placed over a pouring cup to divert the direct application of pressure to molten metal present in the pouring cup. The pressure equalization member allows for increased pressurization rates in such processes, facilitating interdendritic feeding while reducing microporosity and metal penetration defects.

Abstract: A method of producing reticular structures, particularly metallic reticular structures, as well as a device suitable for the production thereof. The method and device enable continuous and/or automated production of such structures, and particularly, large-scale automated production of large-dimensioned reticular structures. A reticulated foam pre-structure is placed into a first container and infiltrated with a refractory material. After solidification, the mold formed by the refractory material is removed from the first container and the foam pre-structure stripped from the mold. The mold is then pre-heated and placed into a second container and infiltrated with a molten substance that forms the reticular structure when solidified. The filled mold may be covered with a solid jacket as a means of controlling the rate and progression of solidification of the molten substance to form a fine-grained, bubble-free structure.

Abstract: An apparatus and method for forming a hollow golf club head is disclosed. The apparatus includes a first mold cavity having depressions formed therein, a second mold cavity having a shape complementary to the exterior of the desired club head, a ceramic core, and wax injecting means. Each depression of the first mold cavity has a depth equal to a desired wall thickness of a corresponding portion of the club head. When the ceramic core is placed in the first mold cavity and wax is injected, wax protuberances, which correspond to the depressions, are formed about the ceramic core. The wax protuberances position the ceramic core in the second mold cavity, where wax is deposited over the majority of the ceramic core.

Abstract: Provided is an evaporative pattern casting process wherein a casting process plan capable of attaining the optimal discharge of generated gas can easily be decided. The present invention is an evaporative pattern casting process for casting a product, which comprises pouring a molten metal in a mold in which a pattern made of an expanded synthetic resin is embedded in molding sand, and evaporating the pattern with the molten metal, while gas generated by evaporation of the pattern is discharged outside the mold through a discharging passage comprising a discharged gas suppressing means, wherein the ventilation of the discharging passage is controlled on the basis of the material and the shape of the pattern and the kind of the molten metal and the temperature of the molten metal.

Abstract: Solid free form fabrication techniques such as fused deposition modeling and three-dimensional printing are used to create a shell used in the manufacture of a dental restoration. Three-dimensional printing includes ink-jet printing a binder into selected areas of sequentially deposited layers of powder. Each layer is created by spreading a thin layer of powder over the surface of a powder bed. Instructions for each layer may be derived directly from a CAD representation of the restoration. The area to be printed is obtained by computing the area of intersection between the desired plane and the CAD representation of the object. All the layers required for an aesthetically sound shell can be deposited concurrently slice after slice and sintered/cured simultaneously.

Abstract: A method for producing a lost mold for titanium casting from a curable embedding compound. The embedding compound contains at least one oxidizable ingredient, such as zirconium. A model of an object to be cast is prepared from a material which can be melted out of the embedding compound. A mold is shaped by embedding the model in the embedding compound. The mold is cured and the embedding compound melted out by heating and holding the mold at a maximum temperature for a period of time. The mold is actively cooled to reduce the cooling time. Preferred embedding compound compositions and time-temperature profiles are disclosed.

Abstract: Apparatus for casting molten metal for the production of metal castings by “lost-foam” technology, comprises: a first container (15) of molten metal, a second container (1) having an upper mouth and containing a bath of granular material (2), immersed in which is a pattern (3, 3a) made of expanded material which can evaporate when contacted by the molten metal, and filling means (14) for supplying the molten metal from the first container (15) to the pattern (3, 3a) in the second container (1), and means for applying a partial vacuum to the second container (1), the means comprising a removable cover (7) which can seal the mouth of the second container (1) in a leaktight manner and which has a first opening (9) with which vacuum-generating means (10, 11) are associated and a second opening (13) with which the filling means (14) are associated in a leaktight manner so that, when the cover (7) is fitted on the second container (1) in a leaktight manner and the vacuum-generating means (10, 11) are ac

Abstract: The application relates to a foamable copolymer resin and a process for preparing the same, which comprises firstly adding an organic peroxide initiator, a modifying aid and a foaming agent to a mixed monomers of methyl methacrylate and styrene so as to constitute a homogenous mixture; at the same tine charging a deionized water into a polymerization reactor and adding a dispersant hydroxy ethyl cellulose or hydroxylpropyl cellulose ether with stirring to produce a homogenous mixture, then sealing the reactor and introducing N2 gas to purge the reactor before the above homogenous monomer mixture is added; after the completion of the reaction the residue is washed with water and dewatered and dried, obtaining foamable pellets.

Abstract: A method for producing a cast article comprises using a porous powder article as a sacrificial pattern. The porous powder article is preferably made using a rapid prototyping process. The porous powder article is used as a sacrificial pattern for a mold into which a molten metal is cast. Some embodiments include a step of proving the porous powder article with a ceramic coating. Methods of making molds and patterns using a porous powder article are also disclosed. The powder comprising the porous powder article may be a metal, ceramic or cermet. In some embodiments, the powder alloys with the molten casting metal. In some other embodiments, the powder and the casting metal form a composite. Sacrificial casting mold patterns comprising porous powder articles and casting molds comprising such sacrificial patterns are also disclosed.

Abstract: A method for casting of metal articles using external pressure and having particular application to lost foam casting of metal articles. A polymeric foam pattern having a configuration corresponding to an article to be cast is placed in an outer flask and the pattern is connected through a polymeric foam gating system to a pouring cup located at the upper end of the flask. The pouring cup has a volume equal to 5% to 75% of the combined volume of the gating system and the pattern. A finely divided inert material, such as sand, is placed in the flask surrounding the pattern and fills the internal cavities within the pattern. The flask containing the pattern is then positioned in an outer pressure vessel having a removable lid and a molten metal is fed into the pouring cup.

Abstract: There is provided a method for producing a dental prosthesis comprising: obtaining three-dimensional digital data relating to a patient's dentition; designing a virtual prosthesis for the dentition using the three-dimensional digital data; transmitting digital data corresponding to the virtual prosthesis to an automated prototyping system; producing a prototype of the dental prosthesis with the automated prototyping system, the prototype made of a material that can be ablated; covering at least the prototype with a hardening material and removing the prototype from within said hardening material to produce a mold for the dental prosthesis; casting the dental prosthesis by filling the mold with a metal and removing the hardening material.

Abstract: A method of forming a ceramic investment shell mold about a fugitive wax pattern of an article comprises coating the pattern with ceramic slurry, applying a ceramic particulate material heated above ambient temperature to the slurry layer, drying the ceramic slurry layer with ceramic particulates thereon, and repeating said coating, applying and drying steps to build up a shell mold on the pattern. The ceramic slurry with ceramic particulates thereon is dried initially dried for a time using relatively low humidity flowing air at an air temperature above about 80 degrees F. and then subsequently for a time using relatively low humidity flowing air at an air temperature not exceeding about 80 degrees F. Ceramic investment shell molds can be built-up in times typically less than 10 hours by practice of the invention with substantially reduced incidence of shell mold cracking during the shell mold building process and subsequent pattern removal operation.

Abstract: A method and apparatus for the lost pattern casting of metals employs an erodable mold including a particulate material and a binder. An erodable backing or coating may be used to support the erodable mold. After a molten metal casting is poured in the mold, the erodable backing and the mold are contacted with a solvent. This cools the molten metal so that it at least partially solidifies to form a casting. At least a part of the mold is removed. Also, the coating or backing may be removed.

Abstract: A cylindrical bushing sleeve or another cast part, in particular a ring carrier for pistons, has a rough surface so that the surrounding cast material can cling to the cast part as required. The rough surface is created by producing the cast part with the aid of a lost mold provided with a particulate layer.

Abstract: Apparatus for the gravity-cast, “lost-foam” casting of metal castings, including a fugitive, pyrolizable foam pattern forming a casting cavity in a bed of loose sand, and a hollow sprue for supplying melt to the casting cavity, wherein the sprue consists essentially of the same metal as is being cast. A high-temperature, porous vent is provided adjacent the discharge end of the metal sprue to expel air from the sprue that would otherwise be trapped therein.

Abstract: Provided is an evaporative pattern casting process which ensures that smooth casting can be carried out without blow-back of a molten metal and a molding product having an excellent casting quality is obtained. The invention relates to an evaporative pattern casting process for casting a product, which comprises pouring a molten metal into a mold provided with a pattern with a through-hole, embedded in molding sand, and evaporating the pattern with the poured molten metal, gradually exhausting the gas generated by the evaporation of the pattern to the outside of the mold through an exhausting path provided with an exhaust gas-controlling means.

Abstract: The present invention is directed to processes for forming styrenic polymers, and their related end uses. In particular, the present invention is directed to processes for preparing patterns for use in metal castings.

Abstract: A new mold solves problems that arise from differential changes in geometry inherent to casting metal in a ceramic mold, by control of the internal morphology between the surfaces of the mold that face the casting, and that face the external environment. Layered fabrication techniques are used to create a ceramic mold. For example, an internal geometry composed of a cellular arrangement of voids may be created within the mold wall. Structures may be designed and fabricated so that the ceramic mold fails at an appropriate time during the solidification and/or cooling of the casting. Thus, the casting itself is not damaged. The mold fails to avoid rupture, or even distortion, of the casting. A thin shell of ceramic defines the casting cavity. This shell must be thin enough to fail due to the stresses induced (primarily compressive) by the metal next to it and partly adherent to it.

Abstract: Method making a multi-wall ceramic core for use in casting airfoils, such as turbine blades and vanes, wherein a fugitive pattern is formed having multiple thin wall pattern elements providing internal wall-forming spaces of a final core, the pattern is placed in a core molding die cavity having a desired core configuration, a fluid ceramic material is introduced into the die cavity about the pattern and between the pattern elements to form a ceramic core, and the core is removed from the die cavity. The fugitive pattern is selectively removed from the core to provide a multi-wall green core. The green core then is fired to develop core strength for casting and used to form an investment casting mold for casting an airfoil.

Abstract: A method of casting a metal article comprising the steps of forming a mold having a mold cavity with a height, a thinwall portion and a base wall portion. The thinwall portion may be less than 0.05 inches thick and free of gating. The method comprises the steps of: positioning the mold in a preheated furnace so that the furnace substantially surrounds the mold and so that a longitudinal axis of the long thin portion of the mold cavity is in an upright orientation; heating the mold in the furnace to a temperature between 1045° C. and 1055° C.; and drawing a vacuum in the furnace. The metal is heated until it is molten and is then poured at a temperature between 1560° land 1570° C. into the mold cavity. The vacuum is then broken and the mold cavity withdrawn from the furnace. The molten metal is allowed to solidify in the mold cavity so that it will solidify with a equiaxed grain structure.

Abstract: An investment casting method using a pattern material with substantially spherical filler particulates is used to produce investment cast components with iproved surface quality, reduced finishing costs, and reduced core breakage. The pattern material comprises substantially spherical particles within the particle size range of about 10 microns to about 70 microns particle diameter, the use of which reduces the number of random, localized surface depressions and pits to improve pattern surface texture and uniformity. Patterns so formed inpart the same improvements to the surface of subsequent investment cast components. The resulting castings exbibit improved as-cast surface finish and reduced random, localized surface pitting, thereby reducing or eliminating expensive post casting surface finishing operations. Moreover, the spherical morphology of the filler particulates reduces injection pressures to fill a pattern die cavity as compared to non-spherical filler particulates.

Abstract: There is provided a method for producing a dental prosthesis comprising: obtaining three-dimensional digital data relating to a patient's dentition; designing a virtual prosthesis for the dentition using the three-dimensional digital data; transmitting digital data corresponding to the virtual prosthesis to an automated prototyping system; producing a prototype of the dental prosthesis with the automated prototyping system, the prototype made of a material that can be ablated; covering at least the prototype with a hardening material and removing the prototype from within said hardening material to produce a mold for the dental prosthesis; casting the dental prosthesis by filling the mold with a metal and removing the hardening material.

Abstract: A method of investment casting a metallic article comprises providing on a fugitive pattern of the article to be cast a relief pattern representing a unique part identification number, investing the pattern in a shell mold, removing the pattern from the shell mold, and introducing molten metallic material into the shell mold to form the solidified cast article having the relief pattern cast-in-place permanently thereon.

Abstract: A fugitive pattern of an article to be investment cast wherein the pattern includes a plurality of locator embossments disposed in an array to provide a datum reference system by which the pattern can be held and positioned by a manipulator, such as for example a gripper device to a computer controlled robotic device, for assembly with another component of the pattern assembly. The datum embossments are located on a portion of the pattern that will be removed from the final metallic casting made to replicate the pattern. The casting includes integral cast datum embossments thereon by which the casting can be held and positioned.

Abstract: A fugitive pattern of an article to be investment cast wherein the pattern includes a plurality of locator embossments disposed in an array to provide a datum reference system by which the pattern can be held and positioned by a manipulator, such as for example a gripper device to a computer controlled robotic device, for assembly with another component of the pattern assembly. The datum embossments are located on a portion of the pattern that will be removed from the final metallic casting made to replicate the pattern. The casting includes integral cast datum embossments thereon by which the casting can be held and positioned.

Abstract: A fugitive pattern of an article to be investment cast wherein the pattern includes a plurality of locator embossments disposed in an array to provide a datum reference system by which the pattern can be held and positioned by a manipulator, such as for example a gripper device to a computer controlled robotic device, for assembly with another component of the pattern assembly. The datum embossments are located on a portion of the pattern that will be removed from the final metallic casting made to replicate the pattern. The casting includes integral cast datum embossments thereon by which the casting can be held and positioned.

Abstract: A tool (40) has a ledge portion (46) and a cutting blade portion (50) for cutting a groove (24, 26, 28) in a wax model (32) for an article of jewelry. The groove is formed after the wax model is formed by mechanical removal of the wax, preferably by cutting with tool (40). The wax model and gems are then placed in an investment mold where the lost wax technique is used to form an article of jewelry with the gems set therein.

Abstract: A method of making a spray formed rapid tool includes the steps of making a model of a desired tool and constructing a ceramic pattern as the inverse of the model. The method also includes the steps of heating the ceramic pattern and thermally spraying a metal material against the ceramic pattern to form a desired tool.

Abstract: A fugitive pattern of an article to be investment cast wherein the pattern includes a plurality of locator embossments disposed in an array to provide a datum reference system by which the pattern can be held and positioned by a manipulator, such as for example a gripper device to a computer controlled robotic device, for assembly with another component of the pattern assembly. The datum embossments are located on a portion of the pattern that will be removed from the final metallic casting made to replicate the pattern. The casting includes integral cast datum embossments thereon by which the casting can be held and positioned.

Abstract: Copolymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, and methyl methacrylate. The polymerization can be carried out in the presence of one or more blowing agents, producing polymers that can be expanded. The methods are useful, for example, in forming expandable polymeric particles. The expandable polymer particles are useful in processes such as forming patterns for lost foam molding techniques.

Abstract: Copolymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, and one or more acrylic monomers. The monomers can be polymerized in the presence of polymeric seeds. The polymerization can be carried out in the presence of one or more blowing agents, producing polymers that can be expanded. The methods are useful, for example, in forming expandable polymeric particles. The expandable polymer particles are useful in processes such as forming patterns for lost foam molding techniques.

Abstract: Method of making a shell mold for casting molten metals or alloys involves forming a thermally collapsible, low density reaction injection molded (RIM) thermosetting polyurethane foam pattern having a shape corresponding to the casting to be made. The pattern is formulated to have an aggregate density (pattern outer skin and pattern cellular core) in the range of about 10 to 15 lbs/ft3 and a smooth continuous as-molded surface devoid of surface connected open cells, dimensional stability over a range of temperatures, and ready, ashless burnout from the shell mold formed thereon without cracking the shell mold. The pattern is free of organometallic catalysts that should not be present in the casting of aerospace superalloys, such as nickel and cobalt base superalloys and titanium. The pattern then is invested without the need for any surface polymer or other film or layer in a shell mold.

Abstract: The invention relates to a camshaft made of cast steel having an inner cavity with a cylindrical inner shape, especially a profiled cylindrical inner shape produced rationally according to a lost-foam casting method known per se. A steel camshaft thus produced exhibits a long service life and can withstand extremely high hertzian surface pressures on its bearing surfaces without any damages.

Abstract: A process for producing dental devices such as teeth is disclosed. Specifically, a process for producing gold dental devices, such as gold denture teeth, is disclosed. The process includes the production of an injection mold based on an impression or mold of a target tooth. The injection mold can then be utilized to produce a hardened polymeric precursor of the product device. In particular, a hardened precursor can be produced from pure polypropylene. The precursor can be used as a model to produce an investment casting mold. The desired product material, for example a gold alloy, can then be cast in the investment casting mold by methods known in the art to produce the final product.

Abstract: A ceramic casting shell mold having a pre-selected shape comprises alternate, repeating layers of a ceramic coating material and a ceramic stucco, defining a total thickness of the shell mold; and a ceramic-based reinforcing sheet disposed in the alternate, repeating layers of coating material and stucco at an intermediate thickness. The ceramic-based reinforcing sheet comprises a one-piece monolithic, integral body, which comprises a pattern of holes that enhance bonding between the ceramic-based reinforcing sheet and adjacent ones of the alternate, repeating layers of ceramic coating material. The ceramic-based reinforcing sheet conforms to the shape of the mold and providing structural reinforcement to the mold.

Abstract: A vaporizable refractory coated pattern assembly is formed having a sprue connected to a plurality of thin wall patterns of articles to be cast. The pattern assembly is supported in a refractory particulate media in an open bottom container that is evacuated to subambient pressure and rotated in a manner to distribute particulates to regions of the refractory coated patterns not yet directly contacted by particulates. The pattern assembly is comprised of relatively dense foam plastic pattern material that imparts increased strength to the thin wall patterns. The sprue includes a vent passage that communicates to a particulate media to vent pattern decomposition vapors thereto in a manner that enables faster replacement of the pattern assembly in the media, despite the use of the relatively dense pattern material.

Abstract: Copolymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, and methyl methacrylate. The polymerization can be carried out in the presence of one or more blowing agents, producing polymers that can be expanded. The methods are useful, for example, in forming expandable polymeric particles. The expandable polymer particles are useful in processes such as forming patterns for lost foam molding techniques.

Abstract: Copolymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, and one or more acrylic monomers. The monomers can be polymerized in the presence of polymeric seeds. The polymerization can be carried out in the presence of one or more blowing agents, producing polymers that can be expanded. The methods are useful, for example, in forming expandable polymeric particles. The expandable polymer particles are useful in processes such as forming patterns for lost foam molding techniques.

Abstract: A method of producing reticular structures, particularly metallic reticular structures, as well as a device suitable for the production thereof. The method and device enable continuous and/or automated production of such structures, and particularly, large-scale automated production of large-dimensioned reticular structures. A reticulated foam pre-structure is placed into a first container and infiltrated with a refractory material. After solidification, the mold formed by the refractory material is removed from the first container and the foam pre-structure stripped from the mold. The mold is then pre-heated and placed into a second container and infiltrated with a molten substance that forms the reticular structure when solidified. The filled mold may be covered with a solid jacket as a means of controlling the rate and progression of solidification of the molten substance to form a fine-grained, bubble-free structure.

Abstract: A thermally highly loaded casting is produced. The casting mold is produced from a slurry using a wax model and a polymer foam which is fixed to the wax model or has been introduced into a cavity. In this way, during the casting process the liquid superalloy also penetrates into the open-cell structure of the casting mold, so that an integral cooling structure is formed during the solidification of the casting. A single-crystal or directionally solidified casting is advantageously produced. It is also conceivable to vary the cell size of the polymer foam, to produce a cooling structure and a base material separately, and to coat the cooling structure with a ceramic protective layer (thermal barrier coating).

Abstract: Copolymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, and one or more acrylic monomers. The monomers can be polymerized in the presence of polymeric seeds. The polymerization can be carried out in the presence of one or more blowing agents, producing polymers that can be expanded. The methods are useful, for example, in forming expandable polymeric particles. The expandable polymer particles are useful in processes such as forming patterns for lost foam molding techniques.

Abstract: The lost foam method of casting a cylinder liner with water jacket comprises the steps of creating a blank identical to the liner desired, with a drain defined therein, from a heat-dissipated material such as styrofoam, coating the blank with core wash, placing the blank into a casting mold, filling the mold and a chamber defined within the blank with sand, pouring hot metal into the mold, extracting the formed metal liner from the mold, draining sand from within the chamber and plugging the sand drain.

Abstract: To produce a thermally highly loaded casting (1, 14, 16, 17) of a thermal turbomachine which is produced using a known casting process, the casting mold is produced from a slurry using a wax model and a polymer foam which is fixed to the wax model or has been introduced into a cavity. In this way, during the casting process the liquid superalloy also penetrates into the open-cell structure of the casting mold, so that an integral cooling structure (7) is formed during the solidification of the casting (1, 14, 16, 17). A single-crystal or directionally solidified casting (1, 14, 16, 17) is advantageously produced. It is also conceivable to vary the cell size of the polymer foam, to produce cooling structure (7) and base material separately and to coat the cooling structure (7) with a ceramic protective layer (thermal barrier coating) (11).

Abstract: The present invention relates to a method of making a molding tool comprising a core die and a cavity die. The method comprises (a) providing a first metal deposit comprising one of the cavity die or the core die, the first metal deposit having a die face, (b) providing a spray forming pattern on a portion of the die face of the first metal deposit,(c) spraying metal particles onto the first metal deposit and the spray forming pattern to form a second metal deposit comprising the other of the cavity die or the core die, and (d) removing the spray forming pattern from the first and second metal deposits.

Abstract: A stereolithography machine is employed to solidify a pattern including a series of stacked grids forming the pattern having an outer skin and inner labyrinth and any number of gates. The hollow pattern is mounted on a central sprue through runners at the gate of the pattern. The pattern is dipped in ceramic slurry and sifted in a refractor grain in order to coat the hollow pattern. The hollow pattern is melted to form a mold.