A method may comprise: placing a probe in a molten metal melt comprising a thixotropic metal alloy; injecting a gas into the molten metal melt to form a saturated slurry, the saturated slurry being at a temperature above a liquidus temperature of the thixotropic metal alloy after injecting the gas; removing the probe from the molten metal melt; and depositing the molten metal melt through an extruder of an additive manufacturing system.

Some variations provide a metal matrix nanocomposite composition comprising metal-containing microparticles and nanoparticles, wherein the nanoparticles are chemically and/or physically disposed on surfaces of the microparticles, and wherein the nanoparticles are consolidated in a three-dimensional architecture throughout the composition. The composition may serve as an ingot for producing a metal matrix nanocomposite. Other variations provide a functionally graded metal matrix nanocomposite comprising a metal-matrix phase and a reinforcement phase containing nanoparticles, wherein the nanocomposite contains a gradient in concentration of the nanoparticles. This nanocomposite may be or be converted into a master alloy. Other variations provide methods of making a metal matrix nanocomposite, methods of making a functionally graded metal matrix nanocomposite, and methods of making a master alloy metal matrix nanocomposite. The metal matrix nanocomposite may have a cast microstructure. The methods disclosed enable various loadings of nanoparticles in metal matrix nanocomposites with a wide variety of compositions.

Methods for repurposing waste materials, such as aluminum powder, are disclosed. A method in accordance with an aspect of the present disclosure may comprise collecting a material in a container, the material comprising oxidized aluminum powder, processing the material, which includes heating the material to melt at least a portion of the oxidized aluminum powder, and forming the processed material into at least one component.

Methods for repurposing waste materials, such as aluminum powder, are disclosed. A method in accordance with an aspect of the present disclosure may comprise collecting a material in a container, the material comprising oxidized aluminum powder, processing the material, which includes heating the material to melt at least a portion of the oxidized aluminum powder, and forming the processed material into at least one component.

The present disclosure relates to a wear part made in a foundry. The wear part has a reinforced portion comprising a ferrous alloy reinforced with metal carbides, nitrides, borides, or intermetallic alloys. The reinforced portion includes inserts of metal carbides, nitrides, metal, or intermetallic compounds manufactured beforehand with a defined geometry and inserted into an infiltrable structure of agglomerated grains including the reagents needed for the formation of metal or intermetallic carbides, nitrides, borides according to an in situ self-propagating thermal reaction initiated during the casting of the ferrous alloy.

Methods for forming a polycrystalline diamond compact (PDC) drill bit from catalyst-free synthesized polycrystalline diamonds are described. The polycrystalline diamonds are deposited within a mold. In some cases, a matrix body material is deposited within the mold, and an infiltration process is performed to bond the polycrystalline diamonds to the matrix body material to form the PDC drill bit. In some cases, a drill bit body is formed within the mold, and forming the drill bit body within the mold includes depositing a layer of matrix body material particles within the mold, depositing an adhesive ink within the mold, and curing the adhesive ink. In some cases, a sintering process is performed after forming the drill bit body to remove at least a portion of the adhesive ink and increase a density of the drill bit body to form the PDC drill bit.

A metal contact of a residential circuit breaker with ordered ceramic microparticles is provided. The metal contact comprises an electrical contact material comprising a metal alloy and ceramic particles to form a metal matrix composite material. Both materials the metal alloy and the ceramic particles are present together as a metal compound but without forming an alloy. The metal compound is a matrix and reinforcement being the ceramic particles such that first the ceramic particles has a sintering step to get a homogeneous preform for the metal compound being porous with a controlled size obtained by pressing a particle size of about few micrometers of the ceramic particles and then a liquid metal infiltration step to provide a homogenous distribution of the metal alloy and the ceramic particles in a three-dimensional open porous arrangement and the homogenous distribution results in ordered microstructures.

A preparation method of a high-strength and high-toughness A356.2 metal matrix composites for a hub is provided, including the following preparation process steps: preparation of a (graphene+HfB.sub.2)-aluminum master alloy wire; A356.2 alloy melting, master alloy addition, refining, and pressure casting; solution and aging treatment; shot blasting, finishing, alkaline/acid cleaning, anodic oxidation, and finished product packaging. In this way, two systems of two-dimensional nano-structure graphene nucleation and in-situ self-nucleation are introduced to complement each other, a second phase of silicon in A356.2 is refined by multi-dimensional scaling, and multi-dimensional nano-phases strengthen the aluminum-based composite material simultaneously. The preparation method solves the problems of limiting the strength, hardness, plasticity and toughness during the application of common A356.2 alloys for a hub, and a graphene/HfB.sub.2/aluminum composite material produced by a low-pressure casting process has an excellent comprehensive performance, so as to achieve a further weight reduction requirement for light weight.

A lightweight liquid metal composition and a method for producing a lightweight liquid metal composition. The composition includes: a liquid metal inclusion; a low-density phase including a plurality of particles; and an elastic polymer. The method includes: combining a low-density phase with a liquid metal to produce a multiphase liquid metal (LM), the low-density phase including a material having a density less than a density of the LM; mixing the multiphase LM with an elastomer to produce an emulsion; and curing the emulsion to produce a lightweight LM composition.

Tools, for example, fixed cutter drill bits, may be manufactured to include hard composite portions having reinforcing particles dispersed in a continuous binder phase and auxiliary portions that are more machinable than the hard composite portions. For example, a tool may include a hard composite portion having a machinability rating 0.2 or less; and an auxiliary portion having a machinability rating of 0.6 or greater in contact with the hard composite portion. The boundary or interface between the hard composite portion and the auxiliary portion may be designed so that upon removal of the most or all of the auxiliary portion the resultant tool has a desired geometry without having to machine the hard composite portion.