A casting method and apparatus are provided for casting a near-net shape article, such as for example a gas turbine engine blade or vane having a variable cross-section along its length. A molten metallic melt is provided in a heated mold having an article-shaped mold cavity with a shape corresponding to that of the article to be cast. The melt-containing mold and mold heating furnace are relatively moved to withdraw the melt-containing mold from the furnace through an active cooling zone where cooling gas is directed against the exterior of the mold to actively extract heat. At least one of the mold withdrawal rate, the cooling gas mass flow rate, and mold temperature are adjusted at the active cooling zone as the melt-containing mold is withdrawn through the active cooling zone to produce an equiaxed grain microstructure along at least a part of the length of the article.

A casting method and apparatus are provided for casting a near-net shape article, such as for example a gas turbine engine blade or vane having a variable cross-section along its length. A molten metallic melt is provided in a heated mold having an article-shaped mold cavity with a shape corresponding to that of the article to be cast. The melt-containing mold and mold heating furnace are relatively moved to withdraw the melt-containing mold from the furnace through an active cooling zone where cooling gas is directed against the exterior of the mold to actively extract heat. At least one of the mold withdrawal rate, the cooling gas mass flow rate, and mold temperature are adjusted at the active cooling zone as the melt-containing mold is withdrawn through the active cooling zone to produce an equiaxed grain microstructure along at least a part of the length of the article.

A cooling system (10) for molding fixtures, and particularly for foundry molds, comprising: water treatment means (II)compressed air generation means (12)means (13) for pressurizing the treated watera device (14) for mixing air with the treated water, and for the controlled ejection of atomized water under pressure toward a cooling circuit (16) of a molding fixture.

A cooling system (10) for molding fixtures, and particularly for foundry molds, comprising: water treatment means (II)compressed air generation means (12)means (13) for pressurizing the treated watera device (14) for mixing air with the treated water, and for the controlled ejection of atomized water under pressure toward a cooling circuit (16) of a molding fixture.

Methods and systems for casting and thermoplastically forming bulk metallic glass articles are described. A molten alloy can be fed into a mold with a three-dimensional shape and a cavity. The mold is configured such that multiple two-dimensional cross sections of the cavity of the mold are different from one another in multiple first mathematical planes intersecting the cavity displaced from one another in a direction normal to the mathematical planes intersecting the cavity. Cooling the molten alloy in the mold provides one or more near net shape bulk metallic glass castings, can be thermoplastically formed using forms at a temperature above Tg to provide a bulk metallic glass article with a desired final shape.

Methods and systems for casting and thermoplastically forming bulk metallic glass articles are described. A molten alloy can be fed into a mold with a three-dimensional shape and a cavity. The mold is configured such that multiple two-dimensional cross sections of the cavity of the mold are different from one another in multiple first mathematical planes intersecting the cavity displaced from one another in a direction normal to the mathematical planes intersecting the cavity. Cooling the molten alloy in the mold provides one or more near net shape bulk metallic glass castings, can be thermoplastically formed using forms at a temperature above Tg to provide a bulk metallic glass article with a desired final shape.

A method for making covetic metal-carbon composites or compositions by electron beam melt heating under vacuum (pressure <10.sup.3 Torr) is described herein. This fabrication method is advantageous, in that it provides oxygen-free covetic materials in a process that allows precise control of the composition of the covetic material to be produced. The method described herein also can be applied to produce multi-element-carbon composites within a metal or alloy matrix, including high melting temperature materials such as ceramic particles or prefabricated nano- or micro-structures, such as carbon nanotubes or graphene compounds. The covetic reaction between metal and carbon takes place under the influence of flowing electrons through the melted metal-carbon precursor. This process creates strong bonding between nanocarbon structure and the metal elements in the melt.

A method for making covetic metal-carbon composites or compositions by electron beam melt heating under vacuum (pressure <10.sup.3 Torr) is described herein. This fabrication method is advantageous, in that it provides oxygen-free covetic materials in a process that allows precise control of the composition of the covetic material to be produced. The method described herein also can be applied to produce multi-element-carbon composites within a metal or alloy matrix, including high melting temperature materials such as ceramic particles or prefabricated nano- or micro-structures, such as carbon nanotubes or graphene compounds. The covetic reaction between metal and carbon takes place under the influence of flowing electrons through the melted metal-carbon precursor. This process creates strong bonding between nanocarbon structure and the metal elements in the melt.

A process in direct chill casting wherein molten metal is introduced into a casting mold and cooled by impingement of a liquid coolant on solidifying metal in a casting pit including a movable platen and an occurrence of a bleed-out or run-out is detected the process including exhausting generated gas from the casting pit; and introducing an inert gas into the casting pit, the inert gas having a density less than a density of air; reducing any flow of the liquid coolant.

A process in direct chill casting wherein molten metal is introduced into a casting mold and cooled by impingement of a liquid coolant on solidifying metal in a casting pit including a movable platen and an occurrence of a bleed-out or run-out is detected the process including exhausting generated gas from the casting pit; and introducing an inert gas into the casting pit, the inert gas having a density less than a density of air; reducing any flow of the liquid coolant.