Abstract: A centrifugal casting method for producing a casting of a metallic material comprises positioning a rotatable assembly comprising a plurality of gates and a plurality of cavities positioned about a sprue chamber. The plurality of gates and the plurality of cavities are positioned to receive molten metallic material from the sprue chamber in a general direction of centrifugal force. Each of the plurality of gates is coupled to one of the plurality of cavities, and at least two of the plurality of cavities are stacked. The method further comprises rotating the rotatable assembly. The method further comprises delivering a supply of molten metallic material to the sprue chamber.

Abstract: An apparatus for melting an electrically conductive metallic material includes a vacuum chamber and a hearth disposed in the vacuum chamber. At least one wire-discharge ion plasma electron emitter is disposed in or adjacent the vacuum chamber and is positioned to direct a wide-area field of electrons into the vacuum chamber, wherein the wide-area electron field has sufficient energy to heat the electrically conductive metallic material to its melting temperature. The apparatus may further include at least one of a mold and an atomizing apparatus which is in communication with the vacuum chamber and is positioned to receive molten material from the hearth.

Abstract: Processes for producing a nickel-titanium alloy are disclosed. The processes are characterized by the production of nickel-titanium alloy articles having improved microstructure. A pre-alloyed nickel-titanium alloy is melted and atomized to form molten nickel-titanium alloy particles. The molten nickel-titanium alloy particles are cooled to form nickel-titanium alloy powder. The nickel-titanium alloy powder is consolidated to form a fully-densified nickel-titanium alloy preform that is hot worked to form a nickel-titanium alloy article. Any second phases present in the nickel-titanium alloy article have a mean size of less than 10 micrometers measured according to ASTM E1245-03 (2008) or an equivalent method.