Abstract: A method of decarburizing a molten alloy may generally comprise injecting a first gas comprising at least one of argon, carbon dioxide, and oxygen through a first fluid-conducting portion of a tuyere into the molten alloy below the surface of the molten alloy, and injecting a second gas comprising at least one of argon and carbon dioxide through a second fluid-conducting portion of the tuyere into the molten alloy below the surface of the molten alloy. The tuyere may comprise an inner portion concentrically aligned within an outer portion to define an annulus therebetween. The first gas may be injected through the inner portion, and the second gas may be injected through the annulus.

Abstract: A method for making a tube is described in which a multi-layer billet is extruded to provide a tube having a wall comprising an inner layer metallurgically bonded to an outer layer.

Abstract: An air hardenable steel alloy is disclosed comprising, in percent by weight: 0.18 to 0.26 carbon; 3.50 to 4.00 nickel; 1.60 to 2.00 chromium; 0 to 0.50 molybdenum; 0.80 to 1.20 manganese; 0.25 to 0.45 silicon; 0 to less than 0.005 titanium; 0 to less than 0.020 phosphorus; 0 up to 0.005 boron; 0 up to 0.003 sulfur; iron; and impurities. The air hardenable steel alloy has a Brinell hardness in a range of 352 HBW to 460 HBW. The air hardenable steel alloy combines high strength, medium hardness and toughness, as compared with certain known air hardenable steel alloys, and finds application in, for example, any of a steel armor, a blast-protective hull, a blast-protective V-shaped hull, a blast-protective vehicle underbelly, and a blast-protective enclosure.

Abstract: Methods of refining the grain size of a titanium alloy workpiece include beta annealing the workpiece, cooling the beta annealed workpiece to a temperature below the beta transus temperature of the titanium alloy, and high strain rate multi-axis forging the workpiece. High strain rate multi-axis forging is employed until a total strain of at least 1 is achieved in the titanium alloy workpiece, or until a total strain of at least 1 and up to 3.5 is achieved in the titanium alloy workpiece. The titanium alloy of the workpiece may comprise at least one of grain pinning alloying additions and beta stabilizing content effective to decrease alpha phase precipitation and growth kinetics.

Abstract: An austenitic stainless steel composition having low nickel and molybdenum and exhibiting high corrosion resistance and good formability. The austenitic stainless steel includes, in weight %, up to 0.20 C, 2.0-6.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 5.0-7.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.1-0.35 N, up to 4.0 W, up to 0.01 B, up to 1.0 Co, iron and impurities. The austenitic stainless steel has a ferrite number less than 11 and an MD30 value less than ?10° C.

Abstract: An austenitic stainless steel having low nickel and molybdenum and exhibiting comparable corrosion resistance and formability properties to higher nickel and molybdenum alloys comprises, in weight %, up to 0.20 C, 2.0-9.0 Mn, up to 2.0 Si, 16.0-23.0 Cr, 1.0-5.0 Ni, up to 3.0 Mo, up to 3.0 Cu, 0.1-0.35 N, up to 4.0 W, up to 0.01 B, up to 1.0 Co, iron and impurities, the steel having a ferrite number of less than 10 and a MD30 value of less than 20° C.

Abstract: A thermo-mechanical treatment process is disclosed. A nickel-base alloy workpiece is heated in a first heating step to a temperature greater than the M23C6 carbide solvus temperature of the nickel-base alloy. The nickel-base alloy workpiece is worked in a first working step to a reduction in area of 20% to 70%. The nickel-base alloy workpiece is at a temperature greater than the M23C6 carbide solvus temperature when the first working step begins. The nickel-base alloy workpiece is heated in a second working step to a temperature greater than 1700° F. (926° C.) and less than the M23C6 carbide solvus temperature of the nickel-base alloy. The nickel-base alloy workpiece is not permitted to cool to ambient temperature between completion of the first working step and the beginning of the second heating step. The nickel-base alloy workpiece is worked to a second reduction in area of 20% to 70%. The nickel-base alloy workpiece is at a temperature greater than 1700° F. (926° C.

Abstract: An aspect of the present disclosure is directed to low-alloy steels exhibiting high hardness and an advantageous level of multi-hit ballistic resistance with low or no crack propagation imparting a level of ballistic performance suitable for military armor applications. Various embodiments of the steels according to the present disclosure have hardness in excess of 550 BHN and demonstrate a high level of ballistic penetration resistance relative to conventional military specifications.

Abstract: One aspect of the present disclosure is directed to a metastable ? titanium alloy comprising, in weight percentages: up to 0.05 nitrogen; up to 0.10 carbon; up to 0.015 hydrogen; up to 0.10 iron; greater than 0.20 oxygen; 14.00 to 16.00 molybdenum; titanium; and incidental impurities. Articles of manufacture including the alloy also are disclosed.

Abstract: A method of reducing the formation of electrically resistive scale on a an article comprising a silicon-containing ferritic stainless subjected to oxidizing conditions in service includes, prior to placing the article in service, subjecting the article to conditions under which silica, which includes silicon derived from the steel, forms on a surface of the steel. Optionally, at least a portion of the silica is removed from the surface to placing the article in service. A ferritic stainless steel alloy having a reduced tendency to form silica on at least a surface thereof also is provided. The steel includes a near-surface region that has been depleted of silicon relative to a remainder of the steel.

Abstract: A method of producing a seamless, composite tubular product includes centrifugally casting a metal or alloy into a tubular workpiece having an inner diameter. The method then centrifugally casts a corrosion resistant alloy in the inner diameter of the tubular workpiece to form a composite tubular workpiece having an inner diameter and an outer diameter. The inner diameter of the composite tubular workpiece is formed of the corrosion resistant alloy, and the outer diameter is formed of the metal or alloy. The method then subjects the composite tubular workpiece to at least about a 25% wall reduction at a temperature below a recrystallization temperature of the workpiece using a metal forming process. The metal forming process includes radial forging, rolling, pilgering, and/or flowforming.

Abstract: A method of assembling a centrifugal casting apparatus includes positioning a wedge on a rotatable axis and positioning at least two molds into sealing engagement with the wedge. Each of the at least two molds includes a front face and defines at least two cavities extending from the front face into the mold. A sprue chamber is defined and is structured to receive molten material, and at least a portion of the sprue chamber is defined by at least a portion of the front faces of the at least two molds.

Abstract: A casting system, apparatus, and method. The casting system can include an energy source and a hearth, which can have a tapered cavity. The tapered cavity can have a first end portion and a second end portion, and the tapered cavity can narrow between the first and second end portions. Further, the tapered cavity can have an inlet at the first end portion that defines an inlet capacity, and one or more outlets at the second end portion that define an outlet capacity. Where the cavity has a single outlet, the outlet capacity can be less than the inlet capacity. Where the cavity has multiple outlets, the combined outlet capacity can match the inlet capacity. Further, the cross-sectional area of the tapered cavity near the inlet can be similar to the cross-sectional area of the inlet.

Abstract: A system and method of processing an alloy ingot or other alloy workpiece to reduce thermal cracking and reduce friction between the workpiece and the forging die may generally comprise positioning a multi-layer pad between the workpiece and the forging die. An article for processing an alloy ingot or other alloy workpiece to reduce thermal cracking also is disclosed. The present disclosure also is directed to an alloy workpieces processed according to the methods described herein, and to articles of manufacture including or made from alloy workpieces made according to these methods.

Abstract: Processes and methods related to producing, processing, and hot working alloy ingots are disclosed. An alloy ingot is formed including an inner ingot core and an outer layer metallurgically bonded to the inner ingot core. The processes and methods are characterized by a reduction in the incidence of surface cracking of the alloy ingot during hot working.

Abstract: Metastable beta titanium alloys and methods of processing metastable ?-titanium alloys are disclosed. For example, certain non-limiting embodiments relate to metastable ?-titanium alloys, such as binary ?-titanium alloys comprising greater than 10 weight percent molybdenum, having tensile strengths of at least 150 ksi and elongations of at least 12 percent. Other non-limiting embodiments relate to methods of processing metastable ?-titanium alloys, and more specifically, methods of processing binary ?-titanium alloys comprising greater than 10 weight percent molybdenum, wherein the method comprises hot working and aging the metastable ?-titanium alloy at a temperature below the ?-transus temperature of the metastable ?-titanium alloy for a time sufficient to form ?-phase precipitates in the metastable ?-titanium alloy. The metastable ?-titanium alloys are not solution heat treated after hot working and prior to aging.

Abstract: Methods for producing alloy strips that demonstrate improved formability are disclosed. The strips have a crystalline microstructure suitable for improved formability in the manufacture of various articles such as panels for plate heat exchangers and high performance tower packing components.

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.