Abstract: A method for preparing aluminum foam sandwich material by rotating friction extrusion and electromagnetic pulse hybrid process includes: step 1: preparing the filler; step 2: processing the filler to prepare a plurality of preforms; step 3: clamping and fixing the plurality of preforms to form a preform assembly; step 4: welding the panel on the surface of the preform assembly to form an non-foaming sandwich material; step 5: heating and foaming the non-foaming sandwich material through a foaming mold; step 6: insulating the foaming mold after completion of foaming; injecting cooling water into the foaming mold after completion of insulation to maintain pressure and shape, forming the aluminum foam sandwich material of the required shape. The aluminum foam sandwich material produced by this method has good interface bonding, no adverse interface reaction, high bending resistance, impact resistance, and excellent sound absorption and insulation properties.

Abstract: Methods for reducing a concentration of hexavalent chromium within a first aluminum slurry by adding a reducing agent to form a second aluminum slurry are provided. The reducing agent causes a chemical reduction reaction with the hexavalent chromium compound of the first aluminum slurry to form a trivalent chromium compound within the second aluminum slurry such that a first weight ratio of hexavalent chromium to trivalent chromium in the first aluminum slurry is decreased to a second weight ratio of hexavalent chromium to trivalent chromium in the second aluminum slurry, with the second weight ratio being less than the first weight ratio.

Abstract: The present disclosure provides methods for generating three-dimensional (3D) objects. The methods may comprise generating a green part corresponding to the 3D object. The green part may comprise a plurality of particles and reactants for conducting a self-propagating reaction. The reactants may be used to conduct a self-propagating reaction that generates heat sufficient to de-bind or pre-sinter the green part. External heat may be supplied to the green part to sinter the plurality of particles, thereby yielding the 3D object. The disclosure also provides methods for generating a 3D object using a resin. The methods may comprise using the resin to generate a green part, heating the green part at a first temperature to decompose a binder in the green part, heating the green part at a second temperature to decompose a polymeric material in the green part, and sintering the green part to yield the 3D object.

Abstract: A method for interconnecting components of an electronic system includes depositing a sintering solution onto a first component to form an interconnection layer, the sintering solution having metal nanoparticles dispersed in a solvent, and a stabilizing agent adsorbed onto the nanoparticles. The nanoparticles have for more than 95.0% of their mass a metal selected from silver, gold, copper and alloys thereof and have a polyhedral shape with an aspect ratio of more than 0.8. The method also includes eliminating, at least partially, solvent from the layer to form an agglomerate in which the stabilizing agent binds nanoparticles together and maintains at least a portion of the nanoparticles at a distance from each other; debinding and sintering the layer by bringing the agglomerate into contact with a destabilizing agent to aggregate and coalesce the nanoparticles and depositing a second component in contact with the layer before or during debinding or sintering.

Abstract: Some variations provide a process for additive manufacturing of a nanofunctionalized metal alloy, comprising: providing a nanofunctionalized metal precursor containing metals and grain-refining nanoparticles; exposing a first amount of the nanofunctionalized metal precursor to an energy source for melting the precursor, thereby generating a first melt layer; solidifying the first melt layer, thereby generating a first solid layer; and repeating many times to generate a plurality of solid layers in an additive-manufacturing build direction. The additively manufactured, nanofunctionalized metal alloy has a microstructure with equiaxed grains.

Abstract: An apparatus and method for manufacturing iron-based mixed powder with excellent flowability is provided. The apparatus includes a hopper which stores and discharges a main raw material of iron-based powder, a transport means which transports the main raw material of iron-based powder discharged from the hopper, a magnetizing means that applies magnetic force to the main raw material transported and falling from the transport means to process the main raw material of iron-based powder into a main raw material bundle in a crumbly type in which the main raw material of iron-based powder is agglomerated with each other, a first mixer in which the main raw material bundle in a magnetized state and an auxiliary raw material of iron-based powder are loaded and mixed while being rotated and transported, and a second mixer in which a first iron-based mixed powder is mixed while being rotated and transported.

Abstract: A method for additively manufacturing a microstructure from a caloric material includes providing a geometry of the microstructure to a processor of an additive manufacturing device, the geometry defining a plurality of microfeatures of the microstructure. The method also includes generating, via the processor, a three-dimensional (3D) model representative of the geometry of the microstructure, wherein one or more of the plurality of microfeatures are represented in the 3D model by a non-arcuate profile. Further, the method includes printing, via the additive manufacturing device, the microstructure from the caloric material according to the 3D model. As such, the non-arcuate profile reduces a file size of the 3D model as compared to an arcuate profile.

Abstract: A method of making a sintered part includes a step of applying a machining process to a compacted part with a tool to make a machined compacted part having a cogwheel shape, and a step of sintering the machined compacted part to make a sintered part, wherein the machining process is such that a surface of the compacted part on a side where the tool exits is supported by a plate member having a tooth pattern with same specifications as a tooth pattern of the cogwheel shape, and the tool is used to machine portions of the compacted part corresponding to tooth spaces of the plate member.

Abstract: A method of forming a near-net shape structure comprises forming a structure comprising non-stoichiometric metal oxide comprising at least one metal and less than a stoichiometric amount of oxygen, and electrochemically reducing the non-stoichiometric metal oxide in an electrochemical cell to form a structure having a near-net shape and comprising the at least one metal having less than about 1,500 ppm oxygen. Related methods of forming a non-stoichiometric metal oxide by sintering, annealing, or additive manufacturing, and forming a near-net shape structure from the non-stoichiometric metal oxide, as well as related electrochemical cells are also disclosed.

Abstract: The successful fabrication of alloy foam (or porous alloy) is very rare, despite their potentially better properties and wider applicability than pure metallic foams. The processing of three-dimensional copper-nickel alloy foams is achieved through a strategic solid-solution alloying method based on oxide powder reduction or sintering processes, or both. Solid-solution alloy foams with five different compositions are successfully created, resulting in open-pore structures with varied porosity. The corrosion resistance of the synthesized copper-nickel alloy foams is superior to those of the pure copper and nickel foams.

Abstract: A three-dimensional monolithic diaphragm tank including a first portion having a first inner surface, a second portion having a second inner surface, and a deformable diaphragm extending from a peripheral junction with the first inner surface and the second inner surface. The first inner surface and the diaphragm defining a first chamber. The second inner surface and the diaphragm defining a second chamber. The first portion having an outlet port in fluid communication with the first chamber, and the second portion having an inlet port in fluid communication with the second chamber. The peripheral junction of the diaphragm and the first inner surface including an integral inner fillet having an inner radius.

Abstract: Disclosed herein, in certain embodiments, are composite materials, methods, tools and abrasive materials comprising a tungsten-based metal composition, a tungsten carbide, and an alloy. In some cases, the composite materials or matrix are resistant to oxidation.

Abstract: Disclosed herein are embodiments of systems and method for processing feedstock materials using microwave plasma processing. Specifically, the feedstock materials disclosed herein pertain to metal powders. Microwave plasma processing can be used to spheroidize the metal powders and form metal nitride or metal carbide powders. The stoichiometry of the metal nitride or metal carbide powders can be controlled by changing the composition of the plasma gas and the residence time of the feedstock materials during plasma processing.

Abstract: One aspect, this invention relates to a carbide-free bainite and retained austenite steel including a composition designed and processed such that the carbide-free bainite and retained austenite steel meets property objectives comprising a yield strength in a range of about 1000-2000 MPa, a uniform ductility, a desired total elongation and hole-expansion ratio, a desired level of weldability and an austenite stability designed to have an austenite start temperature Ms? to be equal to an application temperature in range from about 50° C. to ?50° C. The property objectives are design specifications of the carbide-free bainite and retained austenite steel.

Abstract: A method for the manufacture of a three-dimensional object using a refractory matrix material is provided. The method includes the additive manufacture of a green body from a powder-based refractory matrix material followed by densification via chemical vapor infiltration (CVI). The refractory matrix material can be a refractory ceramic (e.g., silicon carbide, zirconium carbide, or graphite) or a refractory metal (e.g., molybdenum or tungsten). In one embodiment, the matrix material is deposited according to a binder-jet printing process to produce a green body having a complex geometry. The CVI process increases its density, provides a hermetic seal, and yields an object with mechanical integrity. The residual binder content dissociates and is removed from the green body prior to the start of the CVI process as temperatures increase in the CVI reactor. The CVI process selective deposits a fully dense coating on all internal and external surfaces of the finished object.

Abstract: The present invention discloses a preparation process of multi-component spherical alloy powder, which adopts a plasma rotation electrode process (PREP) method to prepare the multi-component spherical alloy powder. The multi-component alloy includes at least one of refractory metals and compounds thereof, specifically including tungsten, molybdenum, tantalum, niobium, rhenium, tungsten carbide, tantalum carbide and the like.

Abstract: Systems and methods for manufacturing sintered materials are disclosed. Metal nano- and microparticles can be sintered to form thin films. The metals are sintered in the presence of a binder such as a tar, e.g., steam cracker tar (SCT), which has strong absorbing and antioxidant properties that allow the metal particles to retain heat. Retention of heat by the binder can allow the sintering to occur at ambient temperatures. In some embodiments, the mixture and/or the resulting films can be used in additive manufacturing processes to build various components from the layers of thin film manufactured from the presently disclosed methods.

Abstract: Provided is a copper powder manufactured by means of a wet method, wherein the absolute value of the zeta potential of the copper powder is at least 20 mV. The copper powder can be manufactured so as to reduce the burden of the steps of crushing a dry cake and classification, and there is a sufficient reduction in residual secondary particles.

Abstract: A non-limiting embodiment of a titanium alloy comprises, in weight percentages based on total alloy weight: 5.5 to 6.5 aluminum; 1.5 to 2.5 tin; 1.3 to 2.3 molybdenum; 0.1 to 10.0 zirconium; 0.01 to 0.30 silicon; 0.1 to 2.0 germanium; titanium; and impurities. A non-limiting embodiment of the titanium alloy comprises a zirconium-silicon-germanium intermetallic precipitate, and exhibits a steady-state creep rate less than 8×10?4 (24 hrs)?1 at a temperature of at least 890° F. under a load of 52 ksi.

Abstract: Methods of pressure assisted melt infiltration of fiber preforms are provided. The fiber preform is provided inside of a pressure vessel. The pressure vessel projects into a molten material contained in a crucible. The pressure vessel has an opening located below a surface of the molten material through which the molten material enters the pressure vessel. An end of the fiber preform contacts the molten material within the pressure vessel. The pressure vessel and crucible are located in a furnace. The molten material is pulled within the pressure vessel by increasing a first pressure at a first port of the furnace so the first pressure is higher than a second pressure at a second port of the pressure vessel. The second port is located above the molten material located within the pressure vessel. The fiber preform is infiltrated with the molten material.