Abstract: A method of producing a casting utilizing an expendable polymeric foam pattern along with unbonded sand having specific thermal properties. The pattern, formed of a material such as polystyrene, has a configuration corresponding to that of the article to be cast. The pattern is placed with an outer flask and unbonded sand surrounds the pattern as well as filling the cavities in the pattern. The sand has a heat diffusivity greater than 1500 J/m.sup.2 /.degree.K./s1/2. The molten hypereutectic aluminum silicon alloy is fed into the flask in contact with the pattern causing the pattern to vaporize with the vapor being entrapped within the interstices of the sand while the molten metal fills the space initially occupied by the foam pattern to produce a cast article. The thermal properties of the sand reduces the particle size of the precipitated primary silicon particles in the casting, thereby increasing the machinability of the casting.

Abstract: A method of producing dimensionally predictable metal castings utilizing an expendable polymeric foam pattern along with unbonded sand having specific thermal properties. The pattern, formed of a material such as polystyrene, has a configuration corresponding to that of the article to be cast. The pattern is placed with an outer flask and unbonded sand surrounds the pattern as well as filling the cavities in the pattern. The sand has a linear expansion of less than 1% from 0.degree. C. to 1600.degree. C., a heat diffusivity greater than 1500 J/m.sup.2 /.degree.K/S1/2, an AFS grain fineness number of 25 to 33, and an AFS base permeability number of 450 to 500. A molten metal, such as an aluminum alloy or a ferrous alloy, is fed into the mold in contact with the pattern causing the pattern to vaporize with the vapor being entrapped within the interstices of the sand while the molten metal fills the space initially occupied by the foam pattern to produce a cast article.

Abstract: A molding lost foam pattern made out of synthetic resin is decomposed and gasified by molten metal. The molding lost foam pattern includes a runner portion foam pattern extending vertically. The runner portion foam pattern includes a hollow portion and a base portion. A plurality of short-sized gate portion foam patterns are provided on external surfaces of the hollow portion of the runner portion foam pattern, and a product portion foam pattern is connected to the external surfaces of the hollow portion through the plurality of short-sized gate portion foam patterns. A method of making the molding lost foam pattern is also disclosed.

Abstract: A metal wood golf clubhead is formed from a mold which includes an external gate into which molten metal is poured and internal gates in the mold cavity which facilitate flow of the molten metal into all portions of the mold cavity. The internal gates are located in the portion of the mold cavity which forms the interior surface of the top of the clubhead.

Abstract: A foamed pattern of a desired part is first formed. The pattern is then dipped into a ceramic slurry and the slurry dried in order to form a shell containing the foamed pattern. A heated bed of a particulate medium is formed around the ceramic shell which causes the pattern to evaporate and form a mold. A molten metal is then introduced into the mold and solidified while being held at an elevated temperature for a period of time to accomplish a desired heat treatment of the metal. With this method, the casting does not have to be subsequently heat treated in a separate operation. It can be removed as an as cast casting, having the desired microstructures.

Abstract: The production of complex cavities inside castings or semi solid forms is effected by forming a core pattern (10) of a low melting point metal in order to provide a rigid metal core pattern (10). The pattern (10) is then nickel coated using either electroplating or electroless nickel plating. The metal core pattern (10) is melted out of the nickel plating to provide a nickel liner core (16). The nickel liner core (16) is placed within a mold or die cavity, and molten metal introduced into the cavity in order to provide a casting or form (30). The casting or form (30) is removed from the cavity and includes therein a plurality of passageways (20) each of which is defined and surrounded by a corrosion resistent nickel liner surface (22).

Abstract: An improved high impact metal clubhead with a unique reinforced composite face wall, increased radius of gyration, and a positive lift air foil surface contour. The composite face wall includes an impact supporting wall rigidified by a pattern of integrally cast reinforcing bars that extend forwardly, rather than rearwardly, from the supporting wall. The reinforced supporting wall is covered by a very hard plastic ball striking insert that is cast in situ over the supporting wall. The increase in radius of gyration is accomplished by extending the heel and toe portions of the clubhead along the face wall further from the geometric center of the head, beyond present day parameters for high impact clubheads. And the positive lift is effected by contouring the top wall of the clubhead downwardly and rearwardly from the base wall more severely almost to the plane of the sole plate, and flattening the rear wall so it is almost co-planar with the sole plate.

Abstract: A pressure molding method and apparatus uses a mold with a casting cavity and a pouring gate through which a molten metal is fed into the casting cavity. After feeding a molten metal into the mold through the pouring gate to fill the casting cavity and pouring gate, a cap member is placed on the mold to bring its open end into contact with a dead head of the molten metal in the pouring gate of the mold so as to form an air-tightly sealed chamber between the cap member and dead head of the molten metal. Pressure is supplied into the sealed chamber to force the molten metal in the mold through the dead head.

Abstract: Disclosed is a single-cast, thin wall structure capable of withstanding impinging gases at temperatures of 4300.degree. F. and higher, and method of making the same. Using a bleed line of the instant invention allows for a decreasing metal pressure with respect to time which prevents any damage to the thin outer mold wall.

Abstract: A method of evaporable foam casting of metal articles, such as engine blocks for internal combustion engines. An evaporable foam pattern having a configuration proportionally identical to the article to be cast is positioned in a mold and a finely divided flowable material, such as sand, surrounds the pattern and fills the internal cavities of the pattern. A molten hypereutectic aluminum-silicon alloy containing 16% to 19.5% by weight of silicon and containing a magnesium content in excess of the magnesium solid solubility limit, is fed into the mold and into contact with the pattern. The heat of the molten metal vaporizes the pattern, with the vapor being trapped within the sand and the molten metal filling the void created by vaporization of the pattern to provide a cast article. The high magnesium content in the alloy produces in the solid state a Mg.sub.

Abstract: A lost foam pattern assembly comprising a crankcase section including first and second mounting surfaces, a right cylinder section which is fixed to the first mounting surface and which includes a primary locator, a left cylinder section which is fixed to the second mounting surface and which includes a primary locator, a transfer passage having an upper end located in the right cylinder section, and a transfer passage having an upper end located in the left cylinder section.

Abstract: A composite aluminum member joining process. A chemical film including potassium and fluorine is formed on an aluminum member or a flux including potassium and fluorine is coated on an aluminum member. The coated aluminum member is buried together with a disposable pattern in a predetermined assembled state in a mold including molding sand. Then, molten aluminum alloy is poured into the mold, thereby molding an aluminum alloy cast member. The mold is decompressed through the molding sand, thereby expelling tar-like substances generated when the disposable pattern comes in contact with the molten aluminum alloy, burns and vaporizes, at least from the boundary surface between the disposable pattern and the molding sand to the molding sand disposed around the disposable pattern and preventing the tar-like substances from interposing between the aluminum member and the aluminum alloy cast member made from the molten aluminum alloy.

Abstract: A method of casting metal using evaporative pattern casting process patterns in combination with a fixture for creating and maintaining a desired configuration in flexible patterns. A pattern is constructed and gently bent to the curvature of a suitable fixture. String or thin wire, which burns off during casting, is used to tie the pattern to the fixture. The fixture with pattern is dipped in a commercially available refractory wash to prevent metal adherence and sticking to the fixture. When the refractory wash is dry, the fixture and pattern are placed in a flask, and sand is added and compacted by vibration. The pattern remains in position, restrained by the fixture. Metal that is poured directly into the pattern replaces the pattern exactly but does not contact or weld to the fixture due to the protective refractory layer. When solid, the casting is easily separated from the fixture. The fixture can be cleaned for reuse in conventional casting cleaning equipment.

Abstract: A squeeze-casting method is taught for manufacturing metal matrix composites which require little or no finishing operations. This method utilizes a combination of techniques, fundamentals of which are found in the investment casting, die casting and metal matrix composite-making arts. The method comprises, forming a wax pattern around the preform and investing the pattern to form a melt-impermeable shell-mold around it. The shell-mold is dewaxed leaving the preform positioned within it. The shell-mold is heated before it is placed in a die cavity of a conventional die caster for high pressure injection of molten metal. Molten metal is poured into the die cavity and pressurized with sufficient pressure and for long enough to impregnate the preform. The metal encapsulates the shell-mold which allows for equilibrated pressures within said die. The pressure is released and the shell-mold is removed from the die cavity before the molten metal in the shell-mold solidifies.

Abstract: A method is disclosed for the casting of metals by the use of a consumable or vaporizable pattern. In this method, a foamed pattern of a desired part is first formed. The pattern is then dipped into a ceramic slurry and the slurry dried in order to form a shell containing the foamed pattern. A bed of a particulate medium heated to a temperature of from 700.degree. to 1000.degree. F. is formed around the ceramic shell to cause the pattern to vaporize without burning and form a mold. A molten metal is then introduced into the mold, solidified and removed from the mold to form a casting. An inert atmosphere can be provided over the bed of heated particulate medium during the vaporization of the pattern to help suppress the burning of the vaporized pattern.

Abstract: A pit defining a machining cavity is positioned downstream of a loading conveyor. A workpiece such as a foam block to be machined into a lost foam pattern for use in full-mold casting is fixedly mounted on an invertable workpiece mount base that is positioned above the machining cavity. The machining cavity houses a cutting unit for cutting, from below, the foam block supported on the workpiece mount base. Chips produced when the foam block is cut by the cutting unit are discharged by a chip discharger disposed beneath the machining cavity. The machining cavity can be substantially closed by the workpiece mount base or the foam block mounted thereon. There may be employed upstream and downstream machining stations each having the machining cavity, the workpiece mount base, and the cutting unit. The workpiece mount base in the upstream machining station is vertically movable, and the upstream and downstream machining stations are interconnected by transfer units.

Abstract: In the Siamese type cylinder block structure, a hollow member having a number of arc guide pieces on both ends is inserted into the upper end between neighboring cylinder bores so as to form a cooling water passage by burying both ends of hollow member in the water jacket core. Insert pins inserted in the guide pieces at both ends of said hollow member communicating with said water jackets to prevent grains of sand injected at high pressure when a water jacket core is manufactured.

Abstract: The production of high precision molds and castings for dental prosthesis and the like is enhanced with a casting ring and sprue former base constructed of a clear expandable thermoplastic. The ring and base are telescopically interlockable with each other to define a vessel containing a mold form strategically disposed therein so that as investment solution poured throughout is able to cure without detracting from the precise measurements of the mold form to provide a true mold from which precisely dimensioned castings are formed.

Abstract: An implant is produced with an open-celled structure at least partly covering its surface. The method uses a positive pattern having a basic pattern with particles bonded to it, the particles covering the areas of the pattern which correspond to the structured surface areas of the implant. The method uses the usual steps of conventional lost positive casting techniques. Importantly, the particles have a base with four to eight pins extending radially from its surface with at least three being connected to the basic pattern (e.g., by adhesive).

Abstract: A mold containing a gasifiable or vaporizable disposable pattern 3, embedded in sand 4 without a binding agent, is fed through its base by a pressurized chamber 6 containing liquid cast metal. The pressure in the chamber 6 is regulated as a function of the surface area/volume ratio of the disposable pattern 3 to prevent the emergence of high-gloss carbon.

Abstract: A method and composition for forming investment casting patterns wherein thermally-collapsible microspheres are incorporated into the pattern composition. The patterns can be made either by conventional pattern forming techniques or by solid imaging techniques. After investing the microsphere containing pattern in the ceramic shell, the pattern and shell are heated, causing a collapse of the microspheres and thereby preventing cracking of the shell. The shell is then heated to burn-out the remaining pattern material and fire the shell, thereby creating a mold.

Abstract: A pattern of an aluminum alloy article made from a foam of an organic substance. The pattern is immersed in a mold of dry sand containing no binder. The mold is filled with molten aluminum alloy from a feeder zone and the alloy is allowed to solidify, thereby creating at least one critical zone in which solidification takes place last. Before the solidified fraction of metal exceeds 40% by weight, an isostatic gas pressure is applied to the mold. The aluminum alloy has a solidification range higher than 30.degree. C. and a ratio R of the distance between the feeder zone and at least one critical zone to half the means thickness of the article over this distance is greater than 10. The isostatic gas pressure being applied is between 0.1 and 0.5 MPa.

Abstract: The pattern, composed of a polymeric material, is formed of three sections joined together by an adhesive along a pair of parallel parting lines. One parting line lies in a plane extending through the axis of an outlet to the engine block and through the axis of a sea water inlet, while the second parting line lies in a plane that extends through the axes of outlets leading to the exhaust manifolds of the V-engine. An inlet opening, through which coolant is received from the engine block, is located in one of the pattern sections and the axis of the inlet opening is normal to the parting lines.

Abstract: An evaporable foam pattern for casting a metal engine block for a two-cycle engine having a direct charge system. The pattern includes a block pattern section having a head end and a crankcase end and a plurality of cylinders extend between the ends. A transfer passage is associated with each cylinder and one end of each transfer passage communicates with the crank-case end of the block, while the opposite end of the transfer passage communicates with the cylinder adjacent the head end. The block pattern section is provided with a plurality of openings each of which provides communication between a transfer passage and the exterior and the openings are bordered by a generally planar surface. The pattern also includes a cover pattern section enclosing the openings in the first section.

Abstract: An improvement to the process for the lost-foam casting of metal articles. According to the process, the casting takes place under a controlled pressure which initially increases at a rate between 0.003 and 0.3 MPa for a first period of at most 5 seconds from the begining of the rise in pressure. The pressure then increases during a second period at a rate higher than the rate of increase during the first period, until the maximum desired pressure is attained.

Abstract: An evaporable foam pattern for casting a metal block for a two-cycle engine. The pattern includes a first pattern section formed of a polymeric material and defining at least one cylinder. The first pattern section has a plurality of elongated slots each of which extends through the section and communicate with a cylinder. Each slot is bordered by an external planar surface. The pattern also includes a group of second pattern sections each formed of polymeric material and having an inner portion extending within a slot and having a peripheral flange disposed in abutting relation with the surface bordering the slot. The abutting surfaces are joined together by an adhesive.

Abstract: A foam pattern assembly includes a parting line, and a surface which is intersected by the parting line and which includes a first surface portion and a second surface portion offset from the first surface portion at the parting line. The surface is leveled so that the first surface portion is not offset from the second surface portion.

Abstract: A cast tubular structure including an integral hose connection element formed thereon is produced by lost foam casting wherein a circular socket seat is formed on a pattern for a body portion of the cast tubular structure and a cylindrical pattern for the integral hose connection element is formed by a mold without vent openings on the mold surface in the area of the cyclindrical pattern corresponding to the hose sealing surface of the cast tubular structure. The pattern sections are joined with the pattern section for the hose connection element sealing within the circular socket seal formed in the body portion of the cast structure. The pattern assembly is coated with a slurry and, after drying, is placed in a casting flask. Molten metal is then poured within the coated pattern assembly dissolving the foam patterns and forming the cast tubular structure.

Abstract: A pattern for molding a die having a shaping panel and an attachment panel is produced by drawing a first rib figure extending from the shaping panel of the die based on configuration figure data which are entered manually or through data transfer into a computer-aided design system based on the configuration of a product, drawing a second rib figure extending from the attachment panel of the die in view of a relationship to a press machine which incorporates the die, and joining the first and second rib figures to each other thereby drawing an entire die figure.

Abstract: A method of making an investment casting by forming a pattern which has the shape of the part which is to be made and forming from the pattern a mold of elastomeric (rubber) material which has a cavity which has the shape of the of the part or casting to be made. Liquid aqueous (water) material is poured into the mold cavity and the mold is cooled so that the material is frozen (ice) to form a solid temporary pattern having the shape of the part. The temporary pattern is coated or invested with ceramic material to form a solid shell about the temporary pattern. The solid temporary pattern is melted and the resulting aqueous material evacuated from the shell to form a cavity which has the shape of the part or casting. The shell cavity is filled with molten metal which is allowed to solidify to form the casting which is removed from the shell.

Abstract: A precision cast connecting rod which has an elongate tubular shank member defining a hollow section for producing desired stiffness to weight characteristics. Piston and crankpin connecting members are attached to opposite ends of the shank member. The connecting members are provided with passages which extend axially therewithin from the hollow section. Defined within the elongate tubular shank member is a radially extending central aperture. A precision casting method for preparing the hollow connecting rod includes forming an elongate core with a locating member positioned at each end thereof and a disk-shaped protuberance extending radially therefrom. The core is secured in a die and defines a cavity therebetween for preparing a pattern of the connecting rod using a molding material which substantially encapsulates the core within the cavity. After removing the pattern from the die, coatings of refractory material are applied to form a shell mold which encrusts the pattern.

Abstract: The pattern is surrounded by packed unbound molding medium within a container. The gaseous material resulting from the evaporation of the pattern is removed from within the container as the gaseous material permeates through the packed unbound molding medium. The outflow of the gaseous material is regulated to control the rate of displacement of the pattern by the molten metal. The removed gaseous material is cleaned and cooled, thereby forming condensate and detoxified gas. Thereafter the condensate, and detoxified gas are discharged.

Abstract: Vacuum countergravity casting apparatus and process employ a container having a peripheral wall defining an open bottom chamber that receives one or more molds or destructible patterns. A first inherently unstable mass of particulates (e.g., binderless sand) is disposed in the chamber about the molds/patterns and a second supportive mass of bonded particulates (e.g., resin-bonded sand) is disposed in the chamber about the molds/patterns beneath the first mass. The second supportive mass is strong enough to support the first mass and preferably the molds/patterns as well as castings ultimately formed as necessary during the casting operation in the event of intentional or unexpected interruption of a negative differential pressure established between the inside and outside of the container.

Abstract: An improvement in the lost foam casting process in which a foam pattern of a part to be cast is immersed in a dry sand mold and the mold is filled with molten metal in order to burn the pattern. According to the improvement, after filling but before the solidified fraction of metal exceeds 40% by weight, an isostatic gas pressure which increases at a predetermined and substantially constant rate to a predetermined maximum value is applied to the mold and maintained at the maximum value until solidification occurs. The rate of increase of pressure is determined as a function of the granulometry of the sand and depth of immersion of the pattern, to cause due to a temporary lag in pressure transmittal through the sand, a rapid and temporary overpressure of the molten metal relative to the sand at the sand/metal interface. The overpressure reaches a maximum value of 0.001 to 0.030 MPa at the beginning of the pressure application and declines as the applied pressure further increases.

Abstract: Disclosed herein is a lost foam pattern assembly comprising a crankcase section including first and second planar surfaces intersecting at an angle defined therebetween, a port cylinder section fixed to the first surface of the crankcase section, and a starboard cylinder section fixed to the second surface of the crankcase section, which port and starboard cylinder sections are fixed to each other along a glue face located in a plane bisecting the angle.

Abstract: A method of forming a hollow cylindrical tube from wax such that a taper exists from one end to the other resulting in different wall thicknesses at either end of the tube, mounting said tube in a vertical position onto a semi-flexible base such that the end of the tube with the greatest wall thickness is in contact with the base, and attaching individual jewelry patterns onto the outside surface of the tube prior to encapsulation by an investment, which is one of the steps in the lost wax casting process of jewelry manufacture.

Abstract: A lost positive pattern comprising an open-pored plastics substrate containing pores with an average width of from one to three millimeters is used, in which, after a negative pattern has been made, the voids which it, as a core, contains are filled with metal by casting and the negative pattern is removed. The production of the negative pattern is preceded by the following method steps in which once the substrate of plastics material has been cleaned, it is wetted throughout with a keying resin film which partially dissolves the structure of its surface and in which at least one coat of an auto-crosslinking two-pack silicone is applied onto and into the whole of the substrate of plastics material to thicken the walls and/or the interlinking webs of the porous substrate of plastics material.

Abstract: A pattern for use in casting a rotatable shaft, such as a crankshaft for an internal combustion engine. The pattern includes an evaporable foam pattern section composed of a material such as polystyrene and having a configuration conforming to the crankshaft to be cast. The evaporable foam pattern section includes a plurality of cranks connected by bearing areas, and tubular metal inserts formed of bearing quality steel are disposed around each bearing area and around the pin areas of the cranks. In the casting process, the pattern is placed in a mold and surrounded with a finely divided material such as sand. When molten ferrous metal is fed into contact with the pattern, the pattern will vaporize with the vapor passing into the interstices of the sand while the molten ferrous metal will occupy the void created by the vaporized foam to produce a cast crankshaft having bearing quality steel inserts at the bearing and pin areas.

Abstract: The thermal shrinkage and pyrolysis rate of plastic foam moldings are successfully controlled by coating the expandable plastic beads used in the preparation of the moldings with varying amounts of substantially water-insoluble inorganic siliceous materials. The plastic foam moldings are useful as patterns in an evaporative casting process, wherein the molding is vaporized and replaced by molten metal.

Abstract: An evaporable foam pattern assembly for casting a housing for a rotary engine. The pattern assembly includes a central rotor chamber pattern section and a pair of end pattern sections which, in the cast engine, are mounted on either side of the central section. The cental pattern section is provided with a central chamber of epitrochoidal shape and the end sections are each formed with a central opening. The outer portion of each central opening is cylindrical in shape, while the inner portion is elliptical and separated from the outer portion by a relief groove. Each end pattern section is provided with an air passage that communicates through the relief groove with the elliptical opening, so that in the assembled cast engine, air introduced into the passage of one of the end sections flows into the rotor chamber of the central section and is discharged from the other end section.

Abstract: A foam pattern assembly for use in forming an engine block in a lost foam casting process, the pattern assembly comprising a base portion including a generally planar front mounting surface having therein a plurality of crankcase-defining cavities and a plurality of intake ports, and a rear mounting surface spaced from the front mounting surface, the base portion partially defining a plurality of transfer passages and a plurality of air intake passages each communicating between a respective one of the intake ports and a respective one of the transfer passages, and a cylinder portion including a generally planar front mounting surface mating with the rear mounting surface on the base portion, the cylinder portion partially defining the air intake passage and partially defining a plurality of cylinder bores each communcating with a respective one of the transfer passages.

Abstract: A method for impregnating an iron product with a hard wear-resistant material surface layer comprises providing a destructible pattern of the desired iron product and applying a paste which comprises a powder of the wear-resistant material and a binder comprising a solution of polyvinyl alcohol onto a portion of the surface of the pattern. The pattern is then coated with a refractory layer by applying a suitable aqueous slurry. A mold is made using the pattern and then an iron melt is cast into the mold thereby forming an iron product having a cast in-place wear-resistant material surface layer. In other embodiments, the method includes the formation of a cavity in the pattern where the binder and particles are introduced into the cavity. In addition, a sheet comprising the binder and particles can be formed, which sheet is then attached to the pattern.

Abstract: A lost foam pattern for an engine block includes a cylinder and an axially extending transfer passage defined by spaced side walls and an inner wall which is outwardly convex.

Abstract: Open-celled metal structures are produced which have walls and webs of uniform strength throughout. The structures may also have an irregular surface pattern. To make a strengthened positive pattern, the method comprises application of at least one layer of a strengthening agent such as poly(methyl methacrylate) or polyester resin to a plastic substrate used for ceramic mold formation. The strengthened positive pattern is embedded in a ceramic mass, and heated to incinerate and remove the plastic substrate, which results in voids in the ceramic mass. Molten metal is poured into the ceramic mass. After solidification, the ceramic mass is removed to form the open-celled metal structure.

Abstract: An organic foam pattern of the article to be cast is immersed in a dry sand mold containing no binder, the mold is filled with molten aluminum or aluminum alloy which replaces the foam and gradually solidifies, and an increasing isostatic gas pressure is simultaneously applied to the mold and to the aluminum or aluminum alloy after filling of the mold is complete. The isostatic gas pressure rises to a maximum value higher than 1.5 MPa and up to 10 MPa, and results in cast articles having improved mechanical characteristics and, in particular, better resistance to fatigue.

Abstract: A molding medium and process for making it, preferably for use in the evaporative pattern casting process, is disclosed. The molding medium comprises, in one embodiment, a base granular molding material having spherically shaped grains wherein the individual grains of the material are coated with a refractory material. Preferably the grains are coated first with a binding agent and then mixed with a refractory material, which may be zirconium oxide. After coating, the material is fired at a high temperature, crushed and screened to size, according to one method. Alternatively, the base molding material may itself be a refractory material, in which case the refractory material is mixed with a binding agent to agglomerate the base material into substantially spherical particles and a refractory coating need not be applied. In either embodiment, substantially spherical free-flowing particles are produced having a low angle of repose.

Abstract: A lost foam casting system (2) is provided with vacuum lift of molten metal (16) to an evaporative foam pattern assembly (8) surrounded by unbonded particulate media such as sand (6) in a flask (4). A gas permeable member (34, 70) formed of randomly oriented ceramic fibers is provided between the sand and a vertical fill passage (20) to apply vacuum from the sand to the fill passage such that molten metal is vacuum lifted through the fill passage to the foam pattern assembly. The foam material is vaporized by the heat of the molten metal as the metal advances upward and is replaced by the metal in the shape of the pattern assembly.

Abstract: The tube is at least two inches long and has successive sections of progressively smaller diameters to produce a correspondingly shaped sprue passage communicating with a pattern cavity in a casting investment, so that fluid casting material passes with increasingly fluid velocity between an inlet and outlet of the sprue passage during the casting process. A bulbous portion of the tube is spaced from its free end, to form a reservoir chamber in the sprue passage, spaced sufficiently from the pattern cavity, so that casting material flowing through the sprue passage attains maximum velocity at the outlet of the passage entering the pattern cavity.

Abstract: In a preferred embodiment, a compound aluminium alloy engine block casting comprises at least a piston-travel region of a cylinder wall section formed of a first alloy, preferably hypereutectic aluminum-silicon alloy, and a remainder including a crankcase section and a water jacket wall formed of a distinct second alloy, preferably hypoeutectic aluminum-silicon alloy. The engine block casting is made by a lost foam process that employs an expendable pattern formed of expanded polystyrene or the like. The pattern comprises a first runner system for casting the first alloy to decompose and replace a portion of the pattern corresponding to the piston-travel region of the casting, and a second runner system for casting the second alloy to decompose and replace the remainder of the pattern. The first alloy and the second alloy are independently but concurrently cast into a singular mold, such that the entire pattern is duplicated, whereupon the alloys merge and fuse to form an integral casting.

Abstract: A method is disclosed for the casting of metals by the use of a consumable or evaporative pattern. In this method, a foamed pattern of a desired part is first formed. The pattern is then dipped into a ceramic slurry and the slurry dried in order to form a shell containing the foamed pattern. A heated bed of a particulate medium is formed around the ceramic shell which causes the pattern to evaporate and form a mold. A molten metal is then introduced into the mold, solidified and removed from the mold to form a casting.