A sintered alloy is produced from mixed powder containing first hard particles, second hard particles, graphite particles, and iron particles. The first hard particles are FeMoNiCoMnSiC-based alloy particles, the second hard particles are FeMoSi-based alloy particles, the mixed powder contains 5 to 50 mass % of the first hard particles, 1 to 8 mass % of the second hard particles, and 0.5 to 1.5 mass % of the graphite particles, when total mass of the first hard particles, the second hard particles, the graphite particles, and the iron particles is set as 100 mass %.

A lightweight, selectively degradable composite material includes a compacted powder mixture of a first powder and a second powder. The first powder comprises first metal particles comprising Mg, Al, Mn, or Zn, having a first particle oxidation potential. The second powder comprises low-density ceramic, glass, cermet, intermetallic, metal, polymer, or inorganic compound second particles. At least one of the first particles and the second particles includes a metal coating layer of a coating material disposed on an outer surface having a coating oxidation potential that is different than the first particle oxidation potential. The compacted powder mixture has a microstructure comprising: a matrix comprising the first metal particles; the second particles dispersed within the matrix; and a network comprising interconnected adjoining metal coating layers that extends throughout the matrix, the lightweight, selectively degradable composite material having a density of about 3.5 g/cm.sup.3 or less.

A lightweight, selectively degradable composite material includes a compacted powder mixture of a first powder and a second powder. The first powder comprises first metal particles comprising Mg, Al, Mn, or Zn, having a first particle oxidation potential. The second powder comprises low-density ceramic, glass, cermet, intermetallic, metal, polymer, or inorganic compound second particles. At least one of the first particles and the second particles includes a metal coating layer of a coating material disposed on an outer surface having a coating oxidation potential that is different than the first particle oxidation potential. The compacted powder mixture has a microstructure comprising: a matrix comprising the first metal particles; the second particles dispersed within the matrix; and a network comprising interconnected adjoining metal coating layers that extends throughout the matrix, the lightweight, selectively degradable composite material having a density of about 3.5 g/cm.sup.3 or less.

The present invention relates to the composition and production of an engineered degradable metal matrix composite that is useful in constructing temporary systems requiring wear resistance, high hardness, and/or high resistance to deformation in water-bearing applications such as, but not limited to, oil and gas completion operations.

Binder compositions for use in forming a bit body of an earth-boring bit include at least one of cobalt, nickel, and iron, and at least one melting point-reducing constituent selected from at least one of a transition metal carbide up to 60 weight percent, a transition metal boride up to 60 weight percent, and a transition metal silicide up to 60 weight percent, wherein the weight percentages are based on the total weight of the binder. Earth-boring bit bodies include a cemented tungsten carbide material comprising tungsten carbide and a metallic binder, wherein the tungsten carbide comprises greater than 75 volume percent of the cemented tungsten carbide material.

There is provided a thermoelectric material including a compound which is formed of an element R belonging to alkaline earth metal and lanthanoid, and an element X belonging to any of Group 13 elements, Group 14 elements, and Group 15 elements. The composition ratio of the element R and the element X is selected to obtain the compound having an AlB.sub.2 type structure.

A powder metal compact is disclosed. The powder metal compact includes a cellular nanomatrix comprising a nanomatrix material. The powder metal compact also includes a plurality of dispersed particles comprising a particle core material that comprises an AlCuMg, AlMn, AlSi, AlMg, AlMgSi, AlZn, AlZnCu, AlZnMg, AlZnCr, AlZnZr, or AlSnLi alloy, or a combination thereof, dispersed in the cellular nanomatrix.

A powder metal compact is disclosed. The powder metal compact includes a cellular nanomatrix comprising a nanomatrix material. The powder metal compact also includes a plurality of dispersed particles comprising a particle core material that comprises an AlCuMg, AlMn, AlSi, AlMg, AlMgSi, AlZn, AlZnCu, AlZnMg, AlZnCr, AlZnZr, or AlSnLi alloy, or a combination thereof, dispersed in the cellular nanomatrix.

The manufacturing method of a porous silicon material of the present disclosure includes a particle forming step of melting a raw material containing Al as a first element in an amount of 50% by mass or more and Si in an amount of 50% by mass or less to obtain a silicon alloy, a pore forming step of removing the first element from the silicon alloy to obtain a porous material, and a heat treatment step of heating the porous material to diffuse elements other than Si to a surface of the porous material.

The manufacturing method of a porous silicon material of the present disclosure includes a particle forming step of melting a raw material containing Al as a first element in an amount of 50% by mass or more and Si in an amount of 50% by mass or less to obtain a silicon alloy, a pore forming step of removing the first element from the silicon alloy to obtain a porous material, and a heat treatment step of heating the porous material to diffuse elements other than Si to a surface of the porous material.