A syntactic metal foam composite that is substantially fully dense except for syntactic porosity is formed from a mixture of ceramic microballoons and matrix forming metal. The ceramic microballoons have a uniaxial crush strength and a much higher omniaxial crush strength. The mixture is continuously constrained while it is consolidated. The constraining force is less than the omniaxial crush strength. The substantially fully dense syntactic metal foam composite is then constrained and deformation worked at a substantially constant volume. The deformation working is typically performed at a yield strength that is adjusted by way of selecting a working temperature at which the yield strength is approximately less than the omniaxial crush strength of the included ceramic microballoons. This deformation causes at least work hardening and grain refinement in the matrix metal.

High-strength, lightweight alloy components, such as automotive components, capable of high temperature performance comprising aluminum, silicon, and iron and/or nickel are provided, along with methods of making such high-strength, lightweight alloy components. A high-energy stream, such as a laser or electron beam, may be selectively directed towards a precursor material to melt a portion of the precursor material in a localized region. The molten precursor material is cooled at a rate of greater than or equal to about 1.010.sup.5 K/second to form a solid high-strength, lightweight alloy component comprising a stable ternary cubic phase having high heat resistance and high strength. The stable ternary phase may be Al.sub.xFe.sub.ySi.sub.z, where x ranges from about 4 to about 5 or about 7.2 to about 7.6, y is about 1.5 to about 2.2, and z is about 1. The stable ternary phase may also be Al.sub.6Ni.sub.3Si.

A method of manufacturing a crystalline aluminum-iron-silicon alloy and a crystalline aluminum-iron-silicon alloy part. An aluminum-, iron-, and silicon-containing composite powder is provided that includes an amorphous phase and a first crystalline phase having a hexagonal crystal structure at ambient temperature. The composite powder is heated at a temperature in the range of 850 C. to 950 C. to transform at least a portion of the amorphous phase into the first crystalline phase and to transform the composite powder into a crystalline aluminum-iron-silicon (AlFeSi) alloy. The first crystalline phase is a predominant phase in the crystalline AlFeSi alloy.

A composite material having an alloy matrix including titanium, aluminum, niobium, manganese, boron, and carbon is disclosed. The composite material includes, by atomic percentage, 40.0% to 50.0% Al, 1.0% to 8.0% Nb, 0.5% to 2.0% Mn, 0.1% to 2.0% B, and 0.01% to 0.2% C. The composite material is doped with a solid lubricant such as MoS.sub.2, ZnO, CuO, hexagonal boron nitride (hBN), WS.sub.2, AgTaO.sub.3, CuTaO.sub.3, CuTa.sub.2O.sub.6, or combinations thereof. Components composed of the composite material exhibit increased ductility at room temperature and reduced fracture tendency, resulting in improved durability.

High-strength, lightweight alloy components, such as automotive components, capable of high temperature performance comprising aluminum, silicon, and iron and/or nickel are provided, along with methods of making such high-strength, lightweight alloy components. A high-energy stream, such as a laser or electron beam, may be selectively directed towards a precursor material to melt a portion of the precursor material in a localized region. The molten precursor material is cooled at a rate of greater than or equal to about 1.010.sup.5 K/second to form a solid high-strength, lightweight alloy component comprising a stable ternary cubic phase having high heat resistance and high strength. The stable ternary phase may be Al.sub.xFe.sub.ySi.sub.z, where x ranges from about 4 to about 5 or about 7.2 to about 7.6, y is about 1.5 to about 2.2, and z is about 1. The stable ternary phase may also be Al.sub.6Ni.sub.3Si.

The disclosure provides aluminum alloys with high tensile strength and appealing cosmetics and improved tensile yield strength. The aluminum alloys include 0.5 to 3.0 wt % Mg and 0.2 to 3.0 wt % Si. The alloys have a weight ratio of Mg to Si ranging from 2 to 4.

In a sliding member, fatigue resistance of a surface layer formed by dispersing a hard material in a soft metal matrix is improved. A sliding member includes a base material layer and a surface layer, the surface layer includes a metal matrix and a hard material harder than the matrix and dispersed in the matrix, the hard material has a gradient in hardness, and the gradient in hardness gradually decreases from an inner side to a surface of the hard material.

Methods of making high-strength, lightweight alloy components capable of high temperature performance comprising aluminum, silicon, and iron and/or nickel are provided. A high-energy stream, such as a laser or electron beam, may be selectively directed towards a precursor material to melt a portion of the precursor material in a localized region. The molten precursor material is cooled at a rate of greater than or equal to about 1.010.sup.5 K/second to form a solid high-strength, lightweight alloy component comprising a stable ternary cubic phase having high heat resistance and high strength. The stable ternary phase may be Al.sub.xFe.sub.ySi.sub.z, where x ranges from about 4 to about 5 or about 7.2 to about 7.6, y is about 1.5 to about 2.2, and z is about 1. The stable ternary phase may also be Al.sub.6Ni.sub.3Si. Materials and components, such as automotive components, made from such methods are also provided.

A structured three-phase composite which include a metal phase, a ceramic phase, and a gas phase that are arranged to create a composite having low thermal conductivity, having controlled stiffness, and a CTE to reduce thermal stresses in the composite when exposed to cyclic thermal loads. The structured three-phase composite is useful for use in structures such as, but not limited to, heat shields, cryotanks, high speed engine ducts, exhaust-impinged structures, and high speed and reentry aeroshells.

A niobium-silicide based alloy and a turbine having at least a turbine component formed from the niobium-silicide based alloy are provided. The niobium-silicide based alloy comprises: between about 14 atomic percent and about 24 atomic percent titanium (Ti); between about 11 atomic percent and about 19 atomic percent silicon (Si); between about 4 atomic percent and about 8 atomic percent chromium (Cr); between about 2 atomic percent and about 6 atomic percent hafnium (Hf); up to about 4 atomic percent aluminum (Al); between about 0.5 atomic percent and about 1 atomic percent tin (Sn); between about 5 atomic percent and about 15 atomic percent tantalum (Ta); between about 1 atomic percent and about 5 atomic percent tungsten (W); up to about 5 atomic percent rhenium (Re); up to about 5 atomic percent zirconium (Zr); up to about 6 atomic percent yttrium (Y); and a balance of niobium (Nb).