Abstract: This invention provides a glassy metal-suction casting method capable of readily and conveniently producing a large-sized amorphous material with excellent properties as an amorphous material. Such an object of the invention is attained by filling a metal material in a mold cooled with water; melting said metal material by using a high-energy heat source which is capable of rapidly melting said metal material; and introducing the resulting molten metal instantaneously into a vertically extending water-cooled mold provided below said mold by using a difference in gas pressure or gravity to move the metal melt at a high speed and attain a high quenching rate to thereby enable the production of a glassy metal ingot of a large size.

Abstract: A levitation melting method and device through which a material having various configurations can be melted through efficient induction heating. First, a starting material(WB), whose outer diameter has been adapted to the inner diameter of a crucible(13), is inserted in crucible(13). The crucible(13) is shielded with argon gas, thereby starting the melting of the material(WB) to molten metal(WM). Subsequently, a suction tube(33) of a mold(31) is inserted into the molten metal(WM) for drawing a part of molten metal(WM) up into the mold(31) for casting. After part of the molten metal(WM) is drawn up, a sliding cover(15) is slid such that a material holder(19) is positioned right above the crucible(13). By opening a sliding plate(35) of the material holder(19), material pieces(WS) are inserted from the material holder(19) into the molten metal(WM) left in the crucible(13).

Abstract: An apparatus and method for casting metal in an evacuated mold cavity. The apparatus has a preferential suction zone through which a mold can be preferentially and effectively evacuated and a suction head sealingly fitting the upper surface of the mold. To the apparatus, is further provided a pressing means for pressing, in cooperation with the suction head, the mold against the inner bottom surface of a mold support chamber. By evacuating the mold through the preferential suction zone while pressing the mold to the bottom of the mold support chamber, a mold cavity is easily filled with a molten metal in such a manner to avoid casting defects such as insufficient filling, blow hole, surface fold, under fill, etc.

Abstract: A vacuum casting apparatus secures gas tightness of the die cavity without welding together a straight-tubular stalk and a flange or flanges, thus permitting an excellent quality casting. A flange is mounted on an outer periphery of a stalk, and secured between a gas-tight chamber and a die, forming a recess bounded by the die, a surface of the flange, and an outer surface of the stalk. The space inside the chamber is evacuated to a first degree of vacuum so that molten metal is withdrawn into the stalk and overflows the end of the stalk, and flows into the recess. Molten metal in the recess cools and solidifies to form a gas-tight seal between the stalk and the flange. Then, the space inside the chamber is evacuated to a second degree of vacuum and molten metal is withdrawn through the stalk and into the cavity of the die.

Abstract: A device for injection casting includes a furnace within which is position a crucible, a bell mounted atop a table into which a mold is positioned and a tube interconnecting the crucible and the mold. A device is provided to sense the level of metal within the crucible; piping is provided into the bell and the furnace for controlling the respective pressures therein and various sensors are provided in the bell, mold, tube and furnace which sense various pressures and temperatures experienced within the device during the casting operation. These sensors provide signals to a control apparatus which controls the pressure inside the furnace in order to fill the mold with metal inside the crucible and regulates the speed and pressure inside the mold. A method of operating the device is also provided.

Abstract: A vacuum casting apparatus secures gas tightness of the die cavity without welding together a straight-tubular stalk and a flange or flanges, thus permitting an excellent quality casting. Two flanges are mounted in a mutually spaced-apart relation on an outer periphery of a stalk, and secured between a gas-tight chamber and a die. The gas-tight chamber is fitted on the die from above to form a gas-tight space between the two flanges. The space is evacuated to a pressure close to an inner pressure formed in a cavity of the die during vacuum casting. Thus, air that intrudes into the cavity of the die through small gaps between the flanges and the stalk is reduced, thereby preventing casting defects which might otherwise result. An end of the stalk inserted into the die is also spread to bring an outer periphery of the stalk into close contact with an inner periphery of a flange mounted on the stalk.

Abstract: A vacuum casting apparatus of the invention in which a melt is introduced into a mold cavity under vacuum, comprises (a) a vacuum vessel having at least one opening at its bottom; (b) a mold disposed within the vacuum vessel and having a mold cavity, a runner having an opening at a position under the opening of the vacuum vessel and extending along at least partially the side of the mold cavity, the mold cavity communicating with the runner through a plurality of filling passages, and a suction recess formed near a riser; and (c) a vacuum means communicating with the vacuum vessel. When the vacuum means evacuates the interior of the vacuum vessel, the mold cavity is rapidly evacuated to result in rapid filling of the cavity with a melt.

Abstract: The machine for filling moulds with metal to be cast, in which a casing is provided comprises a fixed body and a mobile body. The mobile body is driven by a cylinder. The casing can be provided with a vacuum chamber which when closed houses, with the ability to rotate, a sand mould clamped in a central turning body of a support which can be moved by another cylinder towards a lower injector which supplies the mould with the appropriate quantity of cast metal from a lower metering store. A pressure gas is inserted into the metering store through a connection. The metering store receives the cast metal from a larger tank with the assistance of a seal controlled by a level sensor. The machine also includes a metering ladle positioned between a filling plate and the mould itself. The metering ladle has heating elements.

Abstract: In a vacuum casting method, a molding cavity is reduced in pressure to a vacuum, and when a gate is opened, a molten metal which has been raised to a molten metal retaining dome is charged into the molding cavity at a high speed. When a portion of a molten metal held in a molten metal holding furnace is raised to the molten metal retaining dome via a stalk, (1) the rising speed of a portion of the molten metal is set at 5-10 cm/sec, or (2) the rising speed is varied between an early stage of the rising motion and a later stage of the rising motion. In the latter method, the rising speed at the early stage of the rising motion is set at a speed higher than 10 cm/sec, while the rising speed at the later stage of the rising motion is set at 5-10 cm/sec. Due to the rising speed control, air involvement by the rising molten metal is effectively prevented.

Abstract: In a method of vacuum casting wherein when the molten metal previously introduced into a molten metal reservoir is fed into a cavity, the lowest head of the molten metal in the molten metal reservoir is held to be higher than the level of a sprue, so that the cycle time of casting may be shortened and the quality of cast products may be improved. To this end, the interior of the molten metal reservoir is held gas tight while the sprue is opened by a gate member of straight tubular shape.

Abstract: A vacuum casting apparatus includes a plurality of pressure pins arranged in a molding cavity, and at least one pressure pin is located in a portion of the molding cavity farthest from a gate. The pressure pins are operated to pressurize the molding cavity in an order from the pressure pin located farthest from the gate to a pressure pin located nearest to the gate. A cross-sectional area reduced portion can also be formed in a portion of a runner connecting the molding cavity and the molten metal retaining dome. A molten metal in the molding cavity is thereby suppressed from flowing backward into the molten metal retaining dome when being pressurized by the pressure pins, so that the quality of the cast products is improved.

Abstract: In a method of vacuum casting molten metal sucked from a molten metal reservoir into a cavity held under a reduced pressure by opening a gate having been blocking the communication between the molten metal reservoir and the cavity, the trapping of gas and foreign matter in the cavity is effectively prevented. To this end, an accommodation space for accommodating gas and foreign matter is provided in the molten metal reservoir. The accommodation space is provided at a position from which the accommodated matter is not sucked into the cavity.

Abstract: In a vacuum casting method, a mold cavity is reduced in pressure to a vacuum, and when a gate is opened, a molten metal which has been raised to a molten metal retaining dome is charged into the cavity at a high speed. When a portion of a molten metal held in a molten metal holding furnace is raised to the molten metal retaining dome, an upper surface of the molten metal is moved downwardly and upwardly through at least one cycle in the molten metal retaining dome, or a swirl flow is generated in the molten metal in a stalk. Such a unique motion as the downward and upward motion or the swirl flow effectively operates to detach solid metal pieces from an inside surface of the molten metal retaining dome or the stalk to push them to an upper portion of the molten metal. As a result, the detached metal pieces are prevented from being charged into the mold cavity to thereby cause defects in a cast product.

Abstract: A method of producing a metal mold is disclosed. A heat resistant sheet is forcedly brought into close contact with a product configuration surface of a matrix such as a wooden pattern, a resin model, or the like by making use of negative pressure. The matrix is brought into contact with a melt of a low melting-point alloy while that state of close contact is being maintained and the melt is allowed to cool as it is, thereby casting one part of the mold which makes up a pair. The matrix is then removed, and by using the one part of the mold thus cast as a new matrix, this new matrix is brought into contact with the melt of a low melting-point alloy via the heat resistant rubber sheet and is allowed to cool as it is, thereby casting a counterpart of the mold that makes up the pair.

Abstract: Cast vehicle wheels are formed with a re-entrant portion or lightening pocket beneath the tire bead retaining seat. The mold has movable side portions enabling the formation of the re-entrant portion in the wheel. The re-entrant portion reduces the weight of the wheel without adversely affecting the wheel characteristics.

Abstract: A method for the countergravity casting of a melt involves placing a refractory mold in a vacuum chamber defined within a casting box where the mold may be optionally surrounded by support particulates in the vacuum chamber. The mold includes a mold cavity and a serpentine melt inlet passage formed by nested refractory members below the mold cavity and in melt flow communication therewith. The serpentine melt inlet passage is communicated with a fill tube extending from the casting chamber toward an underlying source of melt. The mold/chamber and the source are relatively moved to engage the fill tube and the source. A differential pressure is applied between the mold cavity and the source to urge the melt upwardly through the fill tube and serpentine melt inlet passage into the mold cavity. The mold/chamber and the source are then relatively moved to disengage the fill tube and the source after the mold cavity is filled with the melt.

Abstract: The present invention involves a method and apparatus for making an intermetallic casting (e.g. a titanium, nickel, iron, etc. aluminide casting) wherein a charge of a solid first metal protected from air as required is disposed in a vessel, and a charge of a second metal that reacts exothermically with the first metal is melted in another vessel. The molten second metal is introduced to the vessel containing the charge of the first metal so as to contact the first metal. The first and second metals are heated in the vessel to exothermically react them and form a melt for gravity or countergravity casting into a mold. The exothermic reaction between the first and second metals releases substantial heat that reduces the time needed to obtain a melt ready for casting into a mold. In particular, the exothermic reaction between the first and second metals, in effect, reduces the residence time of the intermetallic melt in the vessel.

Abstract: Titanium based and nickel based castings are made by casting a suitable melt having a relatively low melt superheat into a mold cavity defined by one or more low carbon steel or titanium mold members where the melt solidifies to form the desired casting. The melt super-heat is limited so as not to exceed about 150.degree. F. above the liquidus temperature of the particular melt being cast. For a steel mold, one or more titanium melt inlet-forming members are provided for cooperating with the steel mold members to form an melt ingate that communicates to the mold cavity for supplying the melt thereto in a manner to avoid harmful iron contamination of the melt during casting. The mold body-to-mold cavity volume ratio is controlled between 10:1 to 0.5:1 to minimize casting surface defects and mold wear/damage.

Abstract: A porous preform is placed in a nonporous mold chamber of a pressure vessel. A material is placed in a crucible of the pressure vessel. The pressure vessel is evacuated through a snorkel fluidically connected to the mold chamber and extending therefrom out of the pressure vessel. The material in the crucible is melted. The crucible is placed in fluidic communication with the mold chamber such that the melted material fluidically seals the inside of the mold chamber and the snorkel from the interior of the pressure vessel to fluidically isolate the mold chamber from the interior of the pressure vessel so that a pressure differential exists therebetween.

Abstract: Apparatus and method for countergravity casting a melt employs a particulate mass disposed in a container about a mold having a mold cavity, an ingate passage communicated to the mold cavity for supplying the melt to the mold cavity, and a separate, preformed riser-forming member connected to the mold so as to communicate to an isolated and/or enlarged region of the mold cavity needing additional melt supply during solidification in the mold. The mold ingate passage and a source of the melt are communicated to conduct the melt through the ingate passage to the mold cavity to fill the mold cavity with the melt and form a riser of melt in the particulate mass. The riser of melt provides a source of additional melt for supply, as necessary, to the isolated and/or enlarged region during solidification of the melt in the mold cavity to accommodate melt shrinkage thereat.

Abstract: A vacuum-assisted countergravity casting apparatus 10 includes a casting mold 14 disposed on a cheek mold member 28 and supported within a vacuum box 40. The mold 14 includes bottom feed gates 24 communicating with a cavity 22 within the mold 14. The cheek mold member 28 has distribution channels 30 formed in its upper surface 32 and includes a bottom ingate passage 34. A feed stalk 42 is connected to the ingate passage 34 for immersion into an underlying supply of molten metal 12. Actuation of vacuum pump 52 produces a vacuum within the vacuum chamber 46 and draws the molten metal upwardly to fill the cavity 22. Once filled, the mold 14 is pushed sideways on the cheek 28 by ram 68 causing the feed gates 24 to move out of registry with the distribution channels 30. The molten metal is thereby retained in the cavity 22 without assistance from the vacuum.

Abstract: A process of making a heat sink which includes providing a mold having at least one cavity corresponding to the shape of the article, at least partially evacuating ambient gases from the cavity of the mold, filling the mold with thermally conductive casting material while the mold is at least partially evacuated, and solidifying the material in the mold and removing the resultant molded heat sink.

Abstract: Precision casting of titanium or titanium alloy includes establishing molten metal by induction heating in an assembly formed with water cooled copper segments disposed circlewise on the inside of an induction coil in a state insulated from each other and casting the molten metal into a permeable mold by vacuum casting. The precision casting method uses apparatus including an induction coil, an assembly formed with the aforementioned copper segments, an arrangement for feeding a base metal from the under side thereof and a permeable mold into which the molten base metal in the assembly is transferred by vacuum casting. It is possible to obtain precision castings of metal having high melting points and high actvitiy such as titanium, titanium alloy or the like.

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: Casting apparatus for the vacuum-assisted casting of a melt includes a vacuum box defining a vacuum chamber and a gas permeable casting mold having a first mold portion confronted by the vacuum chamber and a second mold portion unconfronted by the vacuum chamber. The mold includes a mold cavity and a melt inlet that is disposed in the second mold portion for engaging a source of the melt and supplying the melt to the mold cavity. A refractory shield confronts the second mold portion and includes a melt-engaging portion having a melt inlet in melt flow communication with the melt inlet of the mold. A substantially gas impermeable seal is disposed between the refractory shield and the second mold portion for inhibiting ambient gas flow into the vacuum chamber when the vacuum chamber is evacuated during casting. The seal is protected by the refractory shield from heat from the melt when the melt-engaging portion of the refractory shield is engaged with the melt during casting.

Abstract: A casting mold includes an ingate for engaging an underlying source of the melt, an upstanding alloyant-containing reaction chamber having an upper region communicated to the ingate, and an exit gate communicating a lower region of the reaction chamber to a mold cavity. The mold and the source of a melt are relatively moved to engage the ingate and the source. A sufficient relative vacuum is applied to the mold cavity to draw the melt from the source upwardly through the ingate and into the reaction chamber where the melt reacts with alloyant therein. The melt is drawn upwardly to leave at least a portion of the volume of the mold cavity unfilled with melt and to provide a sufficient volume of melt in the reaction chamber to fill the unfilled volume of the mold cavity after disengagement of the mold and the source.

Abstract: Method and apparatus for the differential pressure, countergravity casting of molten metal in shortened cycle times into a casting mold having an inlet passage-forming collar that provides a dam to reduce runout of the melt from the mold during tilting of the mold from the casting position to an inverted solidification position.

Abstract: A wear-resistant cast iron rocker arm or similar machine element is formed by differential pressure, countergravity casting an iron melt of low superheat into a ceramic investment shell mold maintained initially at room temperature and rapidly solidifying the melt therein to provide a wear-resistant, as-cast microstructure throughout the body of the element. The as-cast microstructure comprises a dendritic constituent of austenite or transformed austenite (e.g., pearlite) depending on alloy composition and an interdentritic carbide constituent. Interdendritic ledeburite will also be present if the austenite remains untransformed. The as-cast microstructure of the rocker arm is devoid of graphite.

Abstract: A porous preform is placed within a permanent, nonporous, thin walled mold chamber. The mold chamber is disposed within a pressure vessel. A material is placed in a crucible of the pressure vessel. The pressure vessel is evacuated through a snorkel fluidically connected to the mold chamber. There is means for cooling the snorkel in thermal communication with the snorkel. The material is melted within the crucible. The crucible is placed in fluidic communication with the mold chamber such that the melted material seals the inside of the mold chamber from the pressure vessel to isolate a vacuum within the mold chamber.

Abstract: Casting apparatus for the vacuum-assisted, countergravity casting of a melt comprises a porous, gas permeable casting mold including a mold cavity and a melt inlet communicating the mold cavity to a lower mold portion adapted to engage an underlying source of melt and a vacuum box defining a vacuum chamber confronting the casting mold for evacuating the mold cavity when the lower mold portion and the underlying source of the melt are engaged. A valve member is disposed on the mold in an open position relative to the melt inlet to permit the melt to be drawn upwardly therethrough into the mold cavity when the lower mold portion and the source are engaged with the mold cavity evacuated and is movable to a closed position relative to the melt inlet after the mold cavity is filled with the melt to close off the melt inlet to prevent the melt from flowing out of the mold cavity when the lower mold portion and the source are subsequently disengaged.

Abstract: Casting apparatus comprises a casting mold including first and second elongated pick-up ledges on first and second upstanding mold sides and a mold pick-up mechanism having first and second elongated, pivotal pick-up feet for supportingly engaging the mold ledges to carry the mold through a casting cycle.

Abstract: An expendable pattern of an article to be cast comprises a meltable material that expands upon heating (e.g., a wax pattern). The pattern is invested with particulate mold material to form a thin, layered shell having a wall thickness not exceeding about 0.12 inch. The thin shell wall thickness unexpectedly reduces damage and distortion to the shell during removal of the pattern therefrom by steam autoclaving. After firing, the thin gas permeable shell mold is surrounded by a refractory particulate support media in a vacuum housing. The vacuum housing is then evacuated to evacuate the mold cavity defined by the thin shell and concurrently a pressure is applied to the support media so as to compress the support media about the thin shell to support the shell against casting stresses when molten metal is countergravity cast into the evacuated mold cavity.

Abstract: In vacuum countergravity casting a melt into a mold sealingly engaged to a vacuum container by an elastomeric sealing gasket, the sealing gasket is isolated from the heat of an underlying source of the melt and from contact therewith during casting by substantially binderless refractory particulates, such as loose foundry sand, held in a particulate-receiving space in the container about a lower, melt-engaging portion of the mold by a negative differential pressure established between the inside and outside of the particulate-receiving space.

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: A melt is cast into a gas permeable mold having an upstanding fill sprue that supplies melt to a mold cavity via a lateral ingate. Subambient pressure is applied to the mold fill sprue and to the mold cavity when a lower open end of the sprue and an underlying source of the melt are communicated to urge the melt upwardly to fill the sprue and the mold cavity. Thereafter, the pressure applied to the mold sprue is selectively raised relative to the subambient pressure applied to the mold cavity to cause the melt in the sprue to drain therefrom without siphoning the melt from the melt-filled mold cavity. Pressurized gas can be introduced into the mold sprue as the mold is communicated to the melt source to blow floating slag and other debris away from the region of communication between the sprue lower open end and the source to reduce entry of slag into the mold cavity.

Abstract: A method and apparatus for countergravity casting of molten metal with exclusion of air in a gas-pervious mold sealed in an evacuable chamber having a free end of a fill pipe for the mold cavities projecting therefrom. The fill pipe is moved relative to an enclosed crucible containing the molten metal under an air-free atmosphere of inert gas to project the fill pipe free end into the crucible enclosure to a position below the molten metal so that evacuation of the chamber produces filling of the mold. Entry of air into the crucible enclosure is prevented by maintaining the surface of the molten metal and the ambient atmosphere a sufficient distance apart prior to insertion of the fill pipe to prevent circulating air currents from drawing air down to the metal or by blocking entry into the crucible enclosure. Entry of air can be further prevented by maintaining a sufficient pressure of inert gas in the crucible enclosure and by sealing the upper portion of the fill pipe between the chamber and the mold.

Abstract: A casting mold (e.g., a cope and drag) is disposed on a drag slab having a sprue and a reaction chamber containing an alloyant to be selectively introduced into the melt as it is drawn through the reaction chamber during differential pressure, countergravity casting. A rubber formed between the mold and the drag slab communicates the reaction chamber to a plurality of narrow mold ingates that supply the melt treated (alloyed) in the reaction chamber to the mold cavity during countergravity casting.

Abstract: Casting apparatus comprises a vacuum box having a pair of laterally spaced side walls sealingly engaged to a pair of pick-up members disposed along laterally spaced apart sides of a casting mold. The vacuum box also comprises a pair of spaced end walls sealingly engaged to the casting mold. Sealing engagement of the laterally spaced vacuum box side walls to the pick-up members, rather than to the mold, permits a substantial reduction in the lateral dimension of the mold, thereby substantially reducing the amount of costly mold material (e.g., resin-bonded sand) needed to fabricate the mold for casting and to be disposed of after casting.

Abstract: Molten metal is differential pressure, countergravity cast into a casting mold having a heat conductive chill meter disposed in the ingate to the mold cavity. The chill member accelerates solidification of a plug of the metal in the ingate in the vicinity of the chill member after the mold cavity is filled with molten metal. The plug prevents run-out of molten metal from the mold cavity when the ingate and an underlying molten metal source are disengaged after casting. Accelerated solidification of the plug in the ingate permits early disengagement of the ingate and the molten metal source to shorten casting cycle time.

Abstract: Apparatus and method for the differential pressure, countergravity casting of a melt of molten metal, such as nodular iron, containing a fugative alloyant, such as a magnesium nodularizing agent, susceptible to rapid loss from the melt over time wherein a source of the alloyant is so disposed on a lower portion of each mold as to contact the melt and replenish the alloyant content thereof when the lower mold portion of each mold is immersed in the melt for casting. An effective level of alloyant is thereby maintained in the melt throughout the casting of a plurality of molds in succession from the melt.

Abstract: A method for the differential pressure, countergravity casting of molten metal includes applying a differential pressure to urge molten metal through a constricted inlet passage into a mold cavity of a mold from an underlying molten metal pool, withdrawing the mold from the pool after the mold cavity is filled with the molten metal, holding the molten metal in the mold by combined differential pressure/molten metal surface tension holding action until the molten metal solidifies in the constricted inlet passage of the withdrawn mold or until the mold can be inverted. The differential pressure can be released after the metal solidifies in the inlet passage or after the mold is inverted to allow the molten metal to solidify under ambient pressure.

Abstract: A charge of melt in an amount sufficient to cast only one mold is admitted to a casting basin from a melt-holding chamber. A casting mold is immersed in the freshly admitted charge and the charge is countergravity cast into the mold by establishing a suitable differential pressure between the mold and the charge. After casting, insufficient charge is left in the casting basin to cast the next mold whereupon the casting basin is supplied with the next fresh charge of the melt for casting the next mold. In this way, a fresh charge of melt is cast into each mold in a series of molds. Each charge of melt may be treated (e.g. nodularized) in-situ in the casting basin such that each mold is filled with a freshly treated (nodularized) charge of melt having an effective concentration of the alloyant therein.

Abstract: Particulate mold material, such as binderless foundry sand, is vacuumed upwardly from a particulate bed into an open bottom container about one or more gas permeable molds or destructible patterns in the container to form a casting assembly adapted for immersion in an underlying molten metal pool to effect countergravity casting of molten metal.

Abstract: The casting apparatus and method include a magnetically responsive valve disposed in the molten metal inlet passage of the mold for movement between an open position during mold filling and a closed position after mold filling and during removal of the mold from the underlying molten metal pool to prevent run-out of molten metal from the metal-filled mold cavity. The valve is moved to the closed position by a magnetic force exerted thereon by permanent magnets or an electromagnet disposed around the inlet passage below the valve.

Abstract: In an apparatus for vacuum countergravity casting of molten metal, a gas permeable, self-supporting mold is supported in an inverted casting position in an open bottom container with a particulate bed compacted about the mold. The mold may comprise a mold stack having a plurality of mold members stacked side-by side to form a plurality of mold cavities therebetween. The particulate bed may comprise loose, unbonded particulate compacted in-situ about the mold to support the mold stack in the container and press the mold members sealingly together before, during and after filling with molten metal.

Abstract: A closed mold assembly having a mold cavity therein, an ingate extending from the mold cavity through the mold assembly with an opening having an outer wall for immersion into a bath of molten metal, and an expendable cap fitting around the outer wall of the ingate having a continuously upward tapering dimension to urge the top larger of the molten metal in a bath away from the ingate opening during the immersion process to minimize impurity inclusion in the mold. The expendable cap is preferably made from a non-contaminating sacrificial material intended to be melted after immersion into the molten metal bath without being detrimental to the quality of the workpiece.

Abstract: A melt-holding vessel includes a melt-holding chamber defined by a bottom wall and upstanding side wall of refractory material. The side wall includes one or more insulating air pockets located in such a manner relative to the chamber as to substantially reduce heat loss from the melt in the chamber by conduction through the side wall.

Abstract: A metallic mold (1) comprises two mold halves (3,4) which define between them a mold cavity connected to blowing means (56). The mold (1) is vertically movably mounted on a chassis (18) rigidly supporting an aspiration channel (16). To aspirate the metal, the mold is sealingly applied against the channel which is immersed in the bath (62). After filling of the mold cavity, the material solidifies in a constriction (26) of the channel. This permits raising the chassis (18) without the mold cavity emptying. Then, the mold (1) is raised relative to the channel (16) to break the material in the constriction and to let fall back into the bath the material (68) which was in the channel. Demolding is effected by separating the mold halves from each other.

Abstract: A method of casting a metal matrix composite involves countergravity filling a bottom-gated casting mold from an underlying, initially homogenous, two-phase melt of solid reinforcing particles in a molten metal while continuously inductively stirring the melt during countergravity filling of the mold to minimize subsequent clumping or agglomeration of the reinforcing particles therein during mold filling. After the casting mold is filled, the melt in the mold may be inductively stirred during solidification therein to minimize subsequent clumping or agglomeration of the reinforcing particles in the solidifying melt. A cast metal matrix composite having the reinforcing particles uniformly dispersed in a metal matrix and substantially free of objectionable clusters of the reinforcing particles in the metal matrix is thereby provided.

Abstract: A countergravity casting process involves holding an inherently unstable mass of particulate mold material in an open bottom container around a destructible pattern therein by exerting external fluid pressure, such as atmospheric pressure, on a bottom side of the particulate mass in excess of internal pressure in the container. The container and an underlying molten metal pool are relatively moved to place the bottom side of the particulate mass in the pool. Molten metal is drawn through an ingate to the pattern to destroy and replace the pattern in the particulate mass. When the container and pool are relatively moved to extract the bottom side from the pool after casting, the particulate mold material is held in the container around the metal replacing the pattern by the external/internal pressure differential between the bottom side of the particulate mass and interior of the container.