Abstract: A substrate is coated by applying an essentially pure aluminum first layer to a surface of the substrate. At least a first portion of the first layer is oxidized so as to provide a protective coating of desired properties. The substrate may be a refractory metal-based investment casting core.

Abstract: A method for manufacturing a mold (70), which comprises a step of forming a layer (31) of combustible powdery particles (32) around a wax mold (21), which is a lost pattern, a step of forming a film (51) of a ceramic precursor slurry (52) around the wax mold (21) having powdery particles (32) formed thereon, a step of subjecting the resultant product to a heat treatment, to thereby dewax the wax mold (21), and a step of firing the slurry film (51), to thereby burn and vanish the powdery particles (32) in the slurry film (51) and form a shell (71). The mold (70) has the shell (71) and a porous layer (74) formed on the surface (76) of the cavity of the shell. The mold can be suitably used for manufacturing a porous body (90) having a porous layer (94) on the surface thereof.

Abstract: A process for the manufacture of a part includes the steps of forming a core in a ceramic material, inserting the core into in a wax mold, placing an element on the core thereby forming a spacer between the core and an internal wall of the wax mold, forming a wax model of the part with the core by injecting wax into the mold, forming a shell mold in ceramic material from the wax model, removing the wax, and pouring casting metal into the shell mold, wherein the element is of elongated form and placed on the core in a laying position.

Abstract: A fugitive pattern assembly is made by preforming one or more fugitive patterns of an article to be cast, placing the preformed patterns in an injection die, and injecting fluid gating material into the die to form gating connected to the patterns. The fugitive patterns are disposed in end-to-end and/or side-by-side relation and are interconnected by the gating.

Abstract: Method and apparatus for prolonging the stability (working life) of a ceramic slurry and other aqueous mixture or dispersion containing a liquid silica-bearing or other component as well as the raw liquid silica-bearing component in ambient air over time by providing a gas blanket that reduces exposure to ambient air.

Abstract: A process for manufacturing a blade of a turbomachine using the lost-wax moulding technique, where the blade includes a first central longitudinal cavity and at least one second longitudinal cavity together forming a cooling circuit and communicating with each other at one longitudinal end via a transverse channel. The process includes manufacturing first and second cores corresponding to the cavities, where the two cores each have an end portion, by which they are connected together by an assembly of the mortise and tenon type. The assembly of the two cores is then positioned in a shell mould and the metal poured into the mould.

Abstract: A method to recover wax from wax patterns used in investment casting using a lost wax technique without damaging incorporated ceramic cores is disclosed that includes subjecting the wax pattern to specific conditions. These conditions include chilling a casting tool including the wax pattern and ceramic cores such that a brittle transition temperature for the wax material is approached. Once chilled the wax pattern is subjected to brittle fracture release of the wax from the underlying ceramic cores without damage to those cores.

Abstract: A method for investment casting includes the steps of positioning a base plate relative to a die; molding a first material between the die and at least a first surface portion of the base plate; securing one or more patterns to the base plate, the one or more patterns comprising a second material; applying one or more coating layers over at least portions of the one or more patterns and at least a portion of the first material; substantially removing the first material through an interior receptacle of a manifold body and the second material through an exterior receptacle of the manifold body to leave one or more shells formed by the coating layers; removing said base plate; introducing molten metal to the one or more shells through the interior receptacle of the manifold body; permitting the molten metal to solidify; and destructively removing one or more investment casting molds.

Abstract: A core for casting a metal part having a body with solid portions spaced apart by hollow portions. The body includes at least one support element extending between adjacent solid portions. The support element provides stiffness and strength for the casting core during the casting process. The support element has an optimized shape to prevent the core from fracturing during the casting process and to minimize operating stress in the metal part around the area formed by the support element.

Abstract: Pre-molding of wax or similar sacrificial material over one or more cores facilitates a subsequent molding over a core assembly. Individual cores or groups thereof may be pre-molded in a wax body. One or more such wax bodies may be assembled with other bodies and/or other cores to facilitate a main wax molding of such assembly.

Abstract: A wax or similar material may be molded to a base plate of an investment casting shelling fixture. The molding may provide for enhanced positioning of wax patterns or may provide a precise surface shape for the shell.

Abstract: A method is provided for removing a fugitive pattern, such as wax or other meltable pattern material, residing inside of a refractory mold by discharging condensable vapor such as steam inside the mold to contact and melt the pattern while an exterior of the mold is subjected to a non-condensing gas atmosphere such as air outside of the mold wherein the condensable vapor inside the mold and the atmosphere outside of the mold are at substantially the same pressure. Condensable vapor is condensed inside the mold where the vapor has contacted the pattern while the exterior of the mold remains free of condenate. The condensed vapor and melted pattern material are drained out of the mold. The condensed vapor can be discharged initially inside a hollow sprue of a fugitive pattern assembly to melt the sprue and then inside the mold to melt the patterns of the pattern assembly.

Abstract: In order to more effectively utilise seed crystals 35, 55 to achieve a single crystal grain orientation for a component without the problems of utilising a helix constriction previously necessary to avoid epitaxial grain competition and growth. The present invention creates a wax component pattern 30. This pattern 30 comprises integral sections of wax for a mould component section and for a spacer section with the seed crystal 35 or holder for that crystal therebetween. This pattern 30 is then utilised in order to form a final refractory mould within which the component is formed. By appropriate choice of the spacer section 32, an appropriate spacing between an upper surface of the seed 55 which will be the initial interface with molten castable material to form the component and a chiller surface through which heat is transferred can be determined in order to achieve successful transfer of the seed 55 orientation to the formed component.

Abstract: A method and apparatus are used to cast a number of elements such as turbine engine blades. The blades have an airfoil and a root for securing the blade to a disk. A number of mold sections each have internal surfaces for forming an associated at least one of the elements. The mold sections are assembled and molten alloy is introduced to the assembled mold sections.

Abstract: The invention relates to a method for producing an effectively invisible gemstone setting by casting a wax model of the setting and inserting a flange or post between the stones and into the floor of the setting, or into a depression or aperture on the floor of the setting, in order to secure the stones placed in the wax model of the setting. The flange is shaped so that the majority of its body is hidden beneath the gemstones and so that a narrowed portion of the flange engages the sides or girdles of the gemstones. The upper portion of the flange has sloped sides and may reflect light to and from the crown of the gemstones mounted in the setting.

Abstract: At least one feed core and at least one wall cooling core are assembled with a number of elements of a die for forming a cooled turbine engine element investment casting pattern. A sacrificial material is molded in the die. The sacrificial material is removed from the die. The removing includes extracting a first of the die elements from a compartment in a second of the die elements before disengaging the second die element from the sacrificial material. The first element includes a compartment receiving an outlet end portion of a first of the wall cooling cores in the assembly and disengages therefrom in the extraction.

Abstract: An investment casting pattern is formed by installing a first core to a first element of a molding die to leave a first portion of the first core protruding from the first element. After the installing, the first element is assembled with a feed core and a second element of the molding die so that the first portion contacts the feed core and is flexed. A material is molded at least partially over the first core and feed core.

Abstract: A manufacturing method for a hybrid one-piece design of a wax pattern of a golf club head includes the steps of: prefabricating a first wax pattern in a first molding assembly, the first wax pattern having a connecting portion; inserting the first wax pattern into a first mold cavity of a second molding assembly which has a configuration substantially corresponding to that of a first component of the golf club head; filling liquid wax into a second mold cavity of the second molding assembly which has a configuration substantially corresponding to that of a second component of the golf club head; and cooling the liquid wax in the second mold cavity to form a second wax pattern joined to the connecting portion of the first wax pattern.

Abstract: An investment casting pattern is formed by forming a metallic first core element including at least one recess. The first core element is engaged to at least a mating one of an element of the die and a second core element. The recess serves to retain the first core element relative to the mating one. The die is assembled and a sacrificial material is introduced to the die to at least partially embed the first core element. The recess may be pre-formed prior to cutting the first core element from a larger sheet of material.

Abstract: A composition and method for forming investment casting shells includes using colloidal silica, zircon flour, and fused silica in a slurry which is applied to a pattern. After the slurry is applied to the pattern, it is allowed to partially or completely solidify. After the shell has solidified, the pattern may be melted or otherwise removed. A molten material is introduced into the shell and allowed to cool to form an article. Finally, the shell is broken away or otherwise removed from the article. The improved shell slurry composition and corresponding method minimizes pattern-to-pour cycle times and is environmentally friendly.

Abstract: A method of fabricating a golf club hosel includes the steps of: (1) providing a mold tool having a cavity corresponding to a hosel having a generally cylindrical boss portion coupled to a horizontal leg portion extending radially from the boss portion, wherein the horizontal leg portion has a width that is less than the outside diameter of the boss portion; (2) providing a mold tool insert slideably coupled to the mold tool along a sliding axis generally perpendicular to the horizontal leg portion; (3) sliding the mold tool insert to a first position such that the mold tool insert forms, within said cavity, a surface of the cylindrical portion and a surface of the horizontal leg portion; (4) filling the mold tool cavity with a material (e.g., a wax material); and (5) sliding the mold tool insert to a second position such that the mold tool insert disengages from the material in the mold tool cavity.

Abstract: There is provided a method or process for fabricating a hollow jewelry article which is hollowed or bored out. In accordance with this process, a metal ring model is prepared comprising a solid shank and a metal plate supported along the internal perimeter of the shank by means of a series of spokes extending from the shank. A first metal mold is produced from the metal ring model having the external shape of the jewelry article to be manufactured. From this mold, a wax model of the jewelry article is produced which is first filed down and then cast in order to form a metal model of a core insert; the core insert, like the ring model, has a plate disposed along the perimeter of the shank. This core insert is used to produce a second metal mold. This second mold may then be used repeatedly in order to form a soluble wax core insert model which is then inserted into the cavity of the first mold in order to define the hollow region of the article.

Abstract: A method of making an investment or lost foam casting assembly of a first part movable with respect to a second part includes making first and second separate wax or foam patterns of portions of the first part. Then, a third wax or foam pattern of the second part is made. Next, ceramic core pieces are made. At least one of the core pieces is mounted on the first pattern to form a subassembly. The subassembly is combined with the third pattern so that the core pieces maintain a separation between the third pattern and the first pattern. The first and second patterns are bonded together to trap the subassembly and to form a complete casting assembly.

Abstract: A method of casting including forming a shell mold around a pattern fabricated from an expendable material and then removing the expendable material from the shell mold. The shell mold is located within a housing such that an inlet port of the shell mold communicates with an opening in the housing. A supporting material is provided and substantially fills an open volume between an external surface of the shell mold and an interior surface of the housing. A molten material is then pressure cast through the inlet port and into the shell mold. The invention includes a mold assembly and a casting system useful in practicing the disclosed method.

Abstract: An investment mould process for forming a cast member is described. The process comprises forming a precursor casting (12) from a master mould (10). The master mould (10) has an internal surface (16) defining a space (14) in which the precursor casting (12) can be formed. The surface (16) defines a location indentation (20) to provide a corresponding location projection (3) on the precursor casting (12). A holding member (22) can be inserted into the location projection (3) to hold an internal member (17A, 17B).

Abstract: An investment mould process for forming a cast member is described. The process comprises forming a precursor casting (12) from a master mould (10). The master mould (10) has an internal surface (16) defining a space (14) in which the precursor casting (12) can be formed. The surface (16) defines a location indentation (20) to provide a corresponding location projection (3) on the precursor casting (12). A holding member (22) can be inserted into the location projection (3) to hold an internal member (17A, 17B).

Abstract: An investment mould process for forming a cast member is described. The process comprises forming a precursor casting (12) from a master mould (10). The master mould (10) has an internal surface (16) defining a space (14) in which the precursor casting (12) can be formed. The surface (16) defines a location indentation (20) to provide a corresponding location projection (3) on the precursor casting (12). A holding member (22) can be inserted into the location projection (3) to hold an internal member (17A, 17B).

Abstract: An airfoil, a method of manufacturing an airfoil, and a system for cooling an airfoil is provided. The cooling system can be used with an airfoil located in the first stages of a combustion turbine within a combined cycle power generation plant and involves flowing closed loop steam through a pin array set within an airfoil. The airfoil can comprise a cavity having a cooling chamber bounded by an interior wall and an exterior wall so that steam can enter the cavity, pass through the pin array, and then return to the cavity to thereby cool the airfoil. The method of manufacturing an airfoil can include a type of lost wax investment casting process in which a pin array is cast into an airfoil to form a cooling chamber.

Abstract: A piece of jewelry such a pendant is first cast in wax to provide a wax replica thereof. A gemstone is heated above the melting temperature of the wax replica and is pressed therein. Alternatively, the gemstone is positioned on the surface of the wax replica and pressure is applied to the gemstone to partially embed the gemstone in the wax replica surface at room temperature. The wax replica is then used to from the plaster of Paris mold wherein liquid metal is then poured within the plaster of Paris mold to replace the plaster to form the finished product.

Abstract: A mold is provided for enabling casting of single crystal metallic articles including a part-defining cavity, a sorter passage positioned vertically beneath and in fluid communication with the part-defining cavity, and a seed cavity positioned vertically beneath and in fluid communication with the sorter passage. The sorter passage includes a shape suitable for encouraging a single crystal structure in solidifying molten metal. Additionally, a portion of the mold between the sorter passage and the part-defining cavity includes a notch for facilitating breakage of a cast article proximate the notch during thermal stress build-up, so as to prevent mold breakage or the inclusion of part defects.

Abstract: A connecting method for the wax patterns of the golf club head includes the steps of: prefabricating a first wax pattern and a second wax pattern, the first wax pattern providing with an engaging portion for engaging with the second wax pattern; employing a temperature difference to generate a manufacturing volume tolerance between the first wax pattern and the second wax pattern; combining the engaging portion of the first wax pattern with the second wax pattern; and cooling the first wax pattern to shrink the engaging portion so as to fittingly combine the first wax pattern with the second wax pattern.

Abstract: An apparatus for shelling an investment casting pattern has a tank containing a coating material. There are means for holding the pattern immersed in the coating material. There may be means for vibrating the pattern during immersion of the pattern and a vacuum source coupled to the tank to withdraw air from at least one headspace of the tank.

Abstract: An at least two step heating process is used to strengthen the shell of an investment casting mold including a refractory metal core. The first stage may occur under otherwise oxidizing conditions at a low enough temperature to avoid substantial core oxidation. The second stage may occur under essentially non-oxidizing conditions at a higher temperature.

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 method for casting an airfoil for a turbine engine is provided. The method includes forming a casting core to define a hollow portion in the airfoil and forming a print out region at one end of the casting core. The method also includes coupling the casting core to the print out region with at least one frusto-conical member to facilitate structurally supporting the casting core.

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: A method of making an air boost device, wherein a compressor wheel incorporated therein is re-designed to permit die inserts (20), which occupy the air passage and define the blades (4, 5) during a process of forming a wax pattern (21) of a compressor wheel, to be pulled without being impeded by the blades. This modified blade design enables the automated production of wax patterns (21) using simplified tooling. These wax patterns (21) can be used in a large-scale investment casting process, and produce an economical cast titanium compressor wheel which performs aerodynamically at high boost pressure/RPM.

Abstract: To prevent movement of a ceramic core in a ceramic shell for the investment casting of a turbine blade, the free end of the core has one or more pins embedded therein so that the pins project into both the core and the ceramic shell which is applied over a wax layer. After removal of the wax and firing of the shell, molten metal is cast in the space left by the wax between the core and the shell. After hardening of the metal, the outwardly projecting part of the pins are removed during the machining of the surfaces of the turbine blade blank.

Abstract: Method of making a subcutaneous melt flow-channel in the surface of a fugitive foam pattern used in lost-foam casting process. After a refractory skin has been formed on the surface of a foam pattern, a strip of the skin is treated so as to cause the foam underlying the strip to recede from the strip and leave a groove in its stead. Suitable treatments include (1) heating the strip, or (2) applying a foam solvent thereto that soaks through the skin. In each case, the treatment is such as to cause the foam underlying the treated strip to soften and recede from the strip.

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: A method of casting including forming a shell mold around a pattern fabricated from an expendable material and then removing the expendable material from the shell mold. The shell mold is located within a housing such that an inlet port of the shell mold communicates with an opening in the housing. A supporting material is provided and substantially fills an open volume between an external surface of the shell mold and an interior surface of the housing. A molten material is then pressure cast through the inlet port and into the shell mold. The invention includes a mold assembly and a casting system useful in practicing the disclosed method.

Abstract: One method of the present invention includes introducing a slurry into a mold unit comprised of a mold contained within a casting receptacle and lowering the temperature of the slurry to freeze the slurry and form a freeze-cast substrate while controlling temperature gradients within the mold unit to minimize distortion in the freeze-cast substrate. Another method includes introducing a slurry into a mold unit comprised of a mold contained within a casting receptacle, placing insulation material around at least a portion of the casting receptacle to minimize distortion in the freeze-cast substrate by controlling temperature gradients within the mold unit, and lowering the temperature of the slurry to freeze the slurry to form a freeze-cast substrate.

Abstract: Methods and materials for preparing investment molds useful in pressure infiltration casting of near net-shape metal or metal matrix composite (MMC) components. One embodiment of the invention includes disposing a slurry of an appropriately sized refractory material and a vehicle around a preform or fugitive pattern, removing the bulk of the vehicle, then curing/drying the refractory material to create an investment mold of the invention. Subsequently, pressure infiltration casting with a molten infiltrant using the investment mold permits infiltration of the mold cavity and/or preform without infiltration of the investment mold. As a result, the investment mold readily is removed to provide the near net-shape metal or MMC component. In other embodiments of the invention, a non-fugitive pattern is used, typically with a modified refractory cement of the invention.

Abstract: An investment mould process for forming a cast member is described. The process comprises forming a precursor casting (12) from a master mould (10). The master mould (10) has an internal surface (16) defining a space (14) in which the precursor casting (12) can be formed. The surface (16) defines a location indentation (20) to provide a corresponding location projection (3) on the precursor casting (12). A holding member (22) can be inserted into the location projection (3) to hold an internal member (17A, 17B).

Abstract: A method for casting an airfoil for a turbine engine is provided. The method includes forming a casting core to define a hollow portion in the airfoil and forming a print out region at one end of the casting core. The method also includes coupling the casting core to the print out region with at least one frusto-conical member to facilitate structurally supporting the casting core.

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 for producing a golf club head includes preparing at least two wax models for the golf club head; combining the at least two wax models; coating the combined wax models with a layer of sand mortar to form a sand mortar mold; removing the wax from the sand mortar mold; pouring molten liquid into the sand mortar mold; breaking the sand mortar mold to leave a metal golf club head. The metal golf club head is further cut off any surplus metal and polished to complete a one-piece metal golf club head.

Abstract: In a method of producing a turbine blade in hollow section, an especially low defect or scrap rate is to be ensured. To this end, a first core element is connected via a number of approximately cylindrical spacers to a further core element and/or to a casting mold, the cavities left in the casting mold by the core elements being filled by blade material, and the openings remaining in the turbine blade after the removal of the core elements and the spacers and produced by the spacers being closed by stopper elements.

Abstract: To prevent movement of a ceramic core in a ceramic shell for the investment casting of a turbine blade, the free end of the core has one or more pins embedded therein so that the pins project into both the core and the ceramic shell which is applied over a wax layer. After removal of the wax and firing of the shell, molten metal is cast in the space left by the wax between the core and the shell. After hardening of the metal, the outwardly projecting part of the pins are removed during the machining of the surfaces of the turbine blade blank.

Abstract: The invention relates to a method for producing a cast part of a thermal turbo-machine by way of a known casting process. Between a model mold and a ceramic insert, projections are located on the ceramic insert, whereby the projections have an angle (&agr;, &bgr;) between the center line and the outer edge of the projections of less than 30°, and whereby the projections are used both for the fixation of the insert during the casting process and for the reduction of the notch factor inside the recesses created in the cast part.