A method of fabricating an impregnated fiber assembly, the method including introducing a first suspension including a first powder of solid particles into an inside volume defined by an inside face of a first fiber texture of hollow shape placed in a mold, an outer face of the first fiber texture being present facing a wall of the mold; using a centrifugal force to impregnate the first fiber texture with the first suspension by rotating the mold; after impregnating the first texture, positioning a second fiber texture on the inside face of the first fiber texture to obtain a fiber assembly; introducing a second suspension including a second powder of solid particles into the inside volume after putting the second fiber texture into position; and using a centrifugal force to impregnate the second fiber texture with the second suspension by rotating the mold to obtain an impregnated fiber assembly.

A method of fabricating an impregnated fiber assembly, the method including introducing a first suspension including a first powder of solid particles into an inside volume defined by an inside face of a first fiber texture of hollow shape placed in a mold, an outer face of the first fiber texture being present facing a wall of the mold; using a centrifugal force to impregnate the first fiber texture with the first suspension by rotating the mold; after impregnating the first texture, positioning a second fiber texture on the inside face of the first fiber texture to obtain a fiber assembly; introducing a second suspension including a second powder of solid particles into the inside volume after putting the second fiber texture into position; and using a centrifugal force to impregnate the second fiber texture with the second suspension by rotating the mold to obtain an impregnated fiber assembly.

Carbon fiber reinforced steel matrix composites have carbon fiber impregnated in the steel matrix and chemically bonded to the steel. Chemical bonding is shown by the presence of a unique amorphous carbon layer at the carbon fiber/steel interface, and by canting of steel crystal edges adjacent to the interface. Methods for forming carbon fiber reinforce steel composites include sintering steel nanoparticles around a reinforcing carbon fiber structure, thereby chemically bonding a sintered steel matrix to the carbon fiber. This unique bonding likely contributes to enhanced strength of the composite, in comparison to metal matrix composites formed by other methods.

An aluminum alloy includes, in weight percent, 0.50-1.30% Si, 0.2-0.60% Fe, 0.15% max Cu, 0.5-0.90% Mn, 0.6-1.0% Mg, and 0.20% max Cr, the balance being aluminum and unavoidable impurities. The alloy may include excess Mg over the amount that can be occupied by MgSi precipitates. The alloy may be utilized as a matrix material for a composite that includes a filler material dispersed in the matrix material. One such composite may include boron carbide as a filler material, and the resultant composite may be used for neutron shielding applications.

An aluminum alloy includes, in weight percent, 0.50-1.30% Si, 0.2-0.60% Fe, 0.15% max Cu, 0.5-0.90% Mn, 0.6-1.0% Mg, and 0.20% max Cr, the balance being aluminum and unavoidable impurities. The alloy may include excess Mg over the amount that can be occupied by MgSi precipitates. The alloy may be utilized as a matrix material for a composite that includes a filler material dispersed in the matrix material. One such composite may include boron carbide as a filler material, and the resultant composite may be used for neutron shielding applications.

A structured multi-phase composite which include a metal phase, and a low stiffness, high thermal conductivity phase or encapsulated phase change material, that are arranged to create a composite having high thermal conductivity, having reduced/controlled stiffness, and a low CTE to reduce thermal stresses in the composite when exposed to cyclic thermal loads. The structured multi-phase composite is useful for use in structures such as, but not limited to, high speed engine ducts, exhaust-impinged structures, heat exchangers, electrical boxes, heat sinks, and heat spreaders.

Provided is a method for producing a boron nitride nanotube-reinforced aluminum composite casting, the method being capable of reducing cost. The method for producing a boron nitride nanotube-reinforced aluminum composite casting comprises the steps of: (a) mixing boron nitride nanotubes and a first aluminum matrix and then pelletizing the resulting mixture; (b) heating and subjecting pellets obtained in step (a) to melt mixing to obtain a melt; (c) cooling and solidifying the melt obtained in step (b) to obtain a master batch; and (d) subjecting the master batch obtained in step (c) and the second aluminum matrix to melt mixing, and then cooling and solidifying the resulting mixture.

Provided is a method for producing a boron nitride nanotube-reinforced aluminum composite casting, the method being capable of reducing cost. The method for producing a boron nitride nanotube-reinforced aluminum composite casting comprises the steps of: (a) mixing boron nitride nanotubes and a first aluminum matrix and then pelletizing the resulting mixture; (b) heating and subjecting pellets obtained in step (a) to melt mixing to obtain a melt; (c) cooling and solidifying the melt obtained in step (b) to obtain a master batch; and (d) subjecting the master batch obtained in step (c) and the second aluminum matrix to melt mixing, and then cooling and solidifying the resulting mixture.

A metal matrix composite is provided, including a metal, inorganic particles, and discontinuous fibers. The inorganic particles and the discontinuous fibers are dispersed in the metal. The metal includes aluminum, magnesium, or alloys thereof. The inorganic particles have an envelope density that is at least 30% less than a density of the metal. The metal matrix composite has a lower envelope density than the matrix metal while retaining a substantial amount of the mechanical properties of the metal.

A metal matrix composite is provided, including a metal, inorganic particles, and discontinuous fibers. The inorganic particles and the discontinuous fibers are dispersed in the metal. The metal includes aluminum, magnesium, or alloys thereof. The inorganic particles have an envelope density that is at least 30% less than a density of the metal. The metal matrix composite has a lower envelope density than the matrix metal while retaining a substantial amount of the mechanical properties of the metal.