Abstract: A method of producing autofrettage in a tubular component provides a tubular workpiece having an inner diameter and an outer diameter and provides at least two rollers having a displacement from one another in an axial direction with respect to the workpiece. The method places the workpiece on a mandrel such that the inner diameter is adjacent to the mandrel. The method also compresses the outer diameter of the workpiece with the rollers at a temperature below a recrystallization temperature of the workpiece using a combination of axial and radial forces so that the mandrel contacts the inner diameter and imparts a compressive hoop stress to the inner diameter of the workpiece.

Abstract: An apparatus for casting metals by a nucleated casting technique to create a preform, the apparatus including a mold having a base and a side wall where the base can be moved relative to the side wall to withdraw the preform as it is being created. In various circumstances, portions of a droplet spray created by an atomizing nozzle, i.e., overspray, may accumulate on a top surface of the side wall and prevent or inhibit the preform from being moved relative to the side wall. The atomizing nozzle can be oriented such that the droplet spray passes over the top of the side wall to remelt and remove at least a portion of the overspray that has accumulated thereon. The mold can be rotated such that the overspray formed on a region of or on the entire perimeter of the top surface can pass through the droplet spray and can be removed from the side wall.

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: In one embodiment, a system for treating a gas stream comprising NOx produced from a used or spent acid pickling solution includes a pickling apparatus, a first chamber, and a second chamber. The pickling apparatus includes an inlet adapted for introducing a reducing agent into contact with the acid pickling solution, wherein the reducing agent reacts with free nitric acid in the acid pickling solution to form NOx; and a headspace in which gas comprising NOx collects. The first chamber includes a first inlet communicating with the headspace, a second inlet communicating with a source of ozone, and an interior volume adapted to contact the NOx gas and the ozone. The second chamber may include a third inlet communicating with a source of water vapor, an interior volume adapted to contact the gaseous effluent from the first chamber with the water vapor introduced through the third inlet, and an outlet for collecting solubilized nitric acid from the interior volume of the second chamber.

Abstract: A composite gun barrel comprising: an inner rifled liner tube having an outer surface; and an outer sleeve made from a shape memory alloy and having an inner surface for disposition against the outer surface of the inner rifled liner tube; wherein the inner rifled liner tube is configured for guiding projectiles and the outer sleeve is configured for dampening the firing vibrations encountered by the inner rifled liner tube.

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 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: Processes for the production of nickel-titanium mill products are disclosed. A nickel-titanium alloy workpiece is cold worked at a temperature less than 500° C. The cold worked nickel-titanium alloy workpiece is hot isostatic pressed (HIP'ed).

Abstract: Split pass forging a workpiece to initiate microstructure refinement comprises press forging a metallic material workpiece in a first forging direction one or more times up to a reduction ductility limit of the metallic material to impart a total strain in the first forging direction sufficient to initiate microstructure refinement; rotating the workpiece; open die press forging the workpiece in a second forging direction one or more times up to the reduction ductility limit to impart a total strain in the second forging direction to initiate microstructure refinement; and repeating rotating and open die press forging in a third and, optionally, one or more additional directions until a total amount of strain to initiate microstructure refinement is imparted in an entire volume of the workpiece.

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: A method of processing an alloy workpiece to reduce thermal cracking may comprise spraying a metallic coating material onto at least a portion of a surface of the alloy workpiece to form a surface coating metallurgically bonded to the alloy workpiece. The surface coating may be more ductile than the alloy workpiece and reduces heat loss from the alloy workpiece.

Abstract: A method for straightening an age hardened metallic form includes heating an age hardened metallic form comprising one of a titanium alloy, a nickel alloy, an aluminum alloy, and a ferrous alloy to a straightening temperature of at least 25° F. below the age hardening temperature, and applying an elongation tensile stress for a time sufficient to elongate and straighten the form. The elongation tensile stress is at least 20% of the yield stress and not equal to or greater than the yield stress at the straightening temperature. The straightened form deviates from straight by no greater than 0.125 inch over any 5 foot length or shorter length. The straightened form is cooled while simultaneously applying a cooling tensile stress that balances the thermal cooling stress in the metallic form to thereby maintain a deviation from straight of no greater than 0.125 inch over any 5 foot length or shorter length.

Abstract: A method of processing a non-magnetic alloy workpiece comprises heating the workpiece to a warm working temperature, open die press forging the workpiece to impart a desired strain in a central region of the workpiece, and radial forging the workpiece to impart a desired strain in a surface region of the workpiece. In a non-limiting embodiment, after the steps of open die press forging and radial forging, the strain imparted in the surface region is substantially equivalent to the strain imparted in the central region. In another non-limiting embodiment, the strain imparted in the central and surface regions are in a range from 0.3 inch/inch to 1 inch/inch, and there exists no more than a 0.5 inch/inch difference in strain of the central region compared with the strain of the surface region of the workpiece. An alloy forging processed according to methods described herein also is disclosed.

Abstract: A centrifugal casting apparatus includes a rotatable assembly to rotate about a rotation axis. The rotatable assembly includes a sprue chamber positioned about the rotation axis and is shaped to receive a supply of molten material. A first gate and a second gate are positioned to receive molten material from the sprue chamber in a general direction of centrifugal force. A first cavity and a second cavity are stacked and are respectively positioned to receive molten material from the first gate and the second gate in the general direction of centrifugal force.

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: A method of processing a workpiece to inhibit precipitation of intermetallic compounds includes at least one of thermomechanically processing and cooling a workpiece including an austenitic alloy. During the at least one of thermomechanically working and cooling the workpiece, the austenitic alloy is at temperatures in a temperature range spanning a temperature just less than a calculated sigma solvus temperature of the austenitic alloy down to a cooling temperature for a time no greater than a critical cooling time.

Abstract: A method for producing a single-clad or multiple-clad product includes providing a welded assembly comprising a cladding material disposed on a substrate material. Both the substrate material and the cladding material are individually selected alloys. At least a first edge of the cladding material of the welded assembly does not extend to a first edge of the substrate material and thereby provides a margin between the first edges. A material that is an alloy having hot strength greater than the cladding material is within the margin and adjacent the first edge of the cladding material. The welded assembly is hot rolled to provide a hot rolled band, and the material within the margin inhibits the cladding material from spreading beyond the edge of the substrate material during the hot rolling. In certain embodiments of the methods, the substrate material is stainless steel and the cladding material is nickel or a nickel alloy.

Abstract: A method of processing a metallic material includes introducing an electrically conductive metallic material comprising at least one of a metal and a metallic alloy into a furnace chamber maintained at a low pressure relative to atmospheric pressure. A first electron field having a first area of coverage is generated using at least a first ion plasma electron emitter, and the material within the furnace chamber is subjected to the first electron field to heat the material to a temperature above a melting temperature of the material. A second electron field having a second area of coverage smaller than the first area of coverage is generated using a second ion plasma electron emitter. At least one of any solid condensate within the furnace chamber, any solidified portions of the electrically conductive metallic material, and regions of a solidifying ingot to the second electron field, is subjected to the second electron field, using a steering system.

Abstract: A casting system 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: An embodiment of a method for recovering nitric acid from acid pickling solution includes introducing a treating material comprising at least one chemical into a pickling solution comprising free nitric acid. The treating material reacts with at least a portion of the free nitric acid in the pickling solution and produces NOx. A gas stream comprising at least a portion of the NOx is contacted with ozone, thereby forming oxidation products including nitrogen sesquioxide and nitrogen pentoxide. At least a portion of the nitrogen sesquioxide and nitrogen pentoxide is contacted with water, thereby forming nitric acid, and at least a portion of the nitric acid is collected.