Abstract: A method for producing a silicon ingot having a directional solidification structure comprising the steps of: placing a silicon raw material into a crucible of a melting device constructed by mounting a chill plate on an underfloor heater, mounting a crucible with a large cross-sectional area on the chill plate, providing an overhead heater over the crucible, and surrounding the circumference of the crucible with a heat insulator; heat-melting the silicon raw material by flowing an electric current through the underfloor heater and overhead heater; chilling the bottom of the crucible by halting the electric current through the underfloor heater after the silicon raw material has been completely melted to form a molten silicon; chilling the bottom of the crucible by flowing an inert gas through the chill plate; and intermittently or continuously lowering the temperature of the overhead heater by intermittently or continuously decreasing the electric current through the overhead heater, and an apparatus for pro

Abstract: A mold basket, for supporting a mold, for use in a liquid metal bath furnace with an elevator, comprising a flange for suspending the mold basket from the elevator; and a horizontal plate disposed beneath the flange for supporting the mold, wherein the plate is coupled to the flange with a plurality of vertical tie rods.

Abstract: A device for directional solidification of a fused metal, for example a CoCrAlY alloy, which has been poured into a molding shell, by moving the molding shell out of a heating chamber and by immersing the molding shell in a liquid-metal bath serving as a cooling melt with a lower melting-point than the fused metal in the molding shell, for example tin. The liquid-metal bath is enclosed by several current carrying toroidal coils arranged coaxially relative to one another. For the purpose of orienting the stream filament of the agitated fused metal one or more guide plates are arranged in the space between the lateral circumferential surface of the molding shell and the inner wall of the shell containing the liquid-metal bath which is located opposite the molding shell.

Abstract: Apparatus and method for casting metals and alloys using a pyrometer positioned outside or inside of a casting chamber and relative to a mold heating element in the casting chamber to view a region of a hot melt-filled refractory mold to improve accuracy of the mold temperature readings. The pyrometer is disposed at an elevation outside the casting chamber to view the mold along a viewing path above an induction coil and through an opening in a tubular susceptor disposed about the mold. Alternatively, the tubular susceptor and induction coil both include horizontal openings through which the pyrometer views the melt-filled mold from outside the casting chamber. The pyrometer is positioned to view a uniform profile region of the melt-filled mold having multiple mold cavities as the mold and susceptor are relatively moved.

Abstract: A method of casting a directionally solidified article such as a component of a gas or steam turbine. The casting is performed in a casting furnace comprising a heating chamber, a liquid cooling bath as a cooling chamber and a shell mold. During casting, shell mold is fed with liquid metal and withdrawn from the heating chamber to the cooling chamber while the interior of the casting furnace is supplied with an inert atmosphere of Ar and/or He in the pressure range of 0.01 to 1 atmosphere, with a preferred range of 0.05 to 0.25 atmosphere. The method can provide improved heat transfer across the shell mold allowing a higher withdrawal rate, reduction in defects and/or improvement in properties of the cast articles.

Abstract: In a casting furnace employing a liquid metal bath to allow directional solidification of an article from a melt, and a method of operating such a furnace, a system is provided for lowering the mold from within a heating chamber into a liquid metal bath situated immediately beneath the heating chamber. An automated system is provided for automatically maintaining the level of the liquid metal bath at a relatively constant position immediately beneath the heating chamber, wherein simultaneously upon the level of the bath having risen due to immersion of the mold within the bath, the bath is lowered to thereby permit the level of the liquid metal bath to be maintained in a substantially fixed position.

Abstract: Method as well as apparatus for DS casting using a multi-stage thermal baffle disposed proximate a lower end of a DS casting furnace. The thermal baffle comprises a fixed primary baffle disposed at the lower end of the casting furnace and a secondary baffle initially releasably disposed adjacent and below the primary baffle prior to withdrawal of the melt-filled mold from the casting furnace. The primary baffle includes a primary aperture oriented perpendicular to the mold withdrawal direction and having a cross-sectional configuration tailored to accommodate a relatively large exterior region or profile of the melt-filled mold, such as a relatively wide platform region of a mold for making a turbine blade or vane.

Abstract: In the production of precision castings by centrifugal casting with controlled solidification, a melt is cast under vacuum or shield gas into a pre-heated mold (15) with a central gate (19) and several mold cavities proceeding from the gate toward the outer circumference (Da) of the mold (15). To prevent the formation of shrinkholes and porous areas in the castings, to save energy, and to increase the production rate, the mold (15) is operated at temperatures which decrease from the inside toward the outside. The mold consists of a material or material combination with a coefficient of thermal conductivity lower than that of copper. Before the melt is poured, the mold (15) is heated, starting from the gate (19), by a heating device (20), which projects into the gate, so that the gate (19) reaches a temperature which is a function of the material being cast. Heating is carried out at a rate sufficient to produce a temperature gradient of at least 100° C., preferably of 200-600° C.

Abstract: A casting apparatus, comprising: a heating chamber having an open lower end defined by a periphery; a chill plate having a peripheral region for supporting one or more casting molds thereon and being in movable to move the molds from within the heating chamber to below the lower end of the heating chamber to withdraw the casting molds from the heating chamber; a cooling spool disposed at the periphery of the open lower end of the heating chamber and including a surface area for receiving heat energy radiated from at least one of the heating chamber and the casting molds; and a spool shield disposed at the cooling spool and movable to control an amount of the surface area of the cooling spool available for receiving the heat energy. In another embodiment there is an additional inner cooling spool movable inside the area surrounded by the casting molds for receiving radiant energy. A second spool shield at the inner spool controls its available surface area.

Abstract: A casting apparatus includes a substantially stationary heating chamber having an upper pouring opening and a substantially open lower end; an outer cooling spool disposed at a periphery of the open lower end of the heating chamber; a chill plate having an aperture therethrough and movable through the lower end of the heating chamber; a mold assembly receivable in the chamber and movable through the lower end of the chamber and including peripherally disposed mold cavities defining a substantially interior space accessible through the open lower end of the chamber, an inner cooling spool movable through the aperture of the chill plate and the open lower end of the mold assembly; a first actuator for vertically displacing the chill plate and mold assembly; and a second actuator for vertically displacing the inner cooling spool.

Abstract: A method and apparatus are provided for making high purity and preferably oxygen free substantially void free and inclusion free copper castings such as billets from high purity copper. The castings are particularly useful to make sputtering targets used in sputtering deposition processes in the fabrication of electronic components. The method comprises melting high purity copper in a covered crucible using a non-contaminating heating source such as a coil induction furnace. The melted copper in the crucible is solidified using a specially controlled cooling procedure wherein the bottom of the crucible is cooled so that molten copper is maintained on top of solidified and solidifying copper until the copper is solidified.

Abstract: There is disclosed an apparatus for casting a lead formation, particularly on the lug of a battery component. The lead is streamed over a mould block (20) defining a mould cavity (21) to flood the cavity (21). The flow of lead is maintained to raise the temperature of the block (20), at least adjacent the cavity, to achieve an appropriate working temperature.