The present invention provides a sintered body containing W and WC, having excellent hardness, strength, compactness, and corrosion resistance, without containing W.sub.2C, and capable of being used for the purpose of a cutting tool or a glass molding die, or a seal ring. There is provided a sintered body containing 4 to 50 vol % of tungsten metal as binder phases, 50 to 95 vol % of tungsten carbide (WC), and 0.5 to 5.0 vol % of tungsten oxide (WO.sub.2), in which the tungsten oxide (WO.sub.2) has an average grain size of 5 nm to 150 nm and is present in a sintered body structure at an average density of 5 to 20 particles/μm.sup.2.

Provided is an ultra-fine cemented carbide that has high hardness and exhibits excellent transverse-rupture-strength. The ultra-fine cemented carbide includes a hard phase, containing tungsten carbide (WC) as a main component, in an amount of 80 wt % or more and 99.4 wt % or less, a carbonitride phase, containing titanium carbonitride (Ti(C,N)) as a main component produced by carbonitriding of a titanium (Ti) oxide during sintering, in an amount of 0.1 wt % or more and 10.0 wt % or less, and a binder phase, containing at least one selected from cobalt (Co), nickel (Ni), or iron (Fe) as a main component, in an amount of 0.50 wt % or more and 20 wt % or less, and the binder phase contains chromium carbide (Cr.sub.3C.sub.2) in an amount of 0.10 wt % or more and 20.0 wt % or less based on all of the binder phase, and in the ultra-fine cemented carbide, the hard phase, the carbonitride phase, and the binder phase total 100 wt %, WC after the sintering has an average grain size of 1.0 μm or less, the nitrogen content is 0.10 wt % or more and 1.25 wt % or less, and the carbon content is 4.80 wt % or more and 6.30 wt % or less.

A method may include controlling, by a computing device, an energy source to form a melt pool at a build surface; and controlling, by the computing device, a material delivery device to direct a powder at the melt pool to form the seal fin comprising a metal matrix composite on the build surface, wherein the metal matrix composite comprises a matrix material and a reinforcement phase.

A nanoparticle or agglomerate which contains connected multi-walled spherical fullerenes coated in layers of graphite. In different embodiments, the nanoparticles and agglomerates have different combinations of: a high mass fraction compared to other carbon allotropes present, a low concentration of defects, a low concentration of elemental impurities, a high Brunauer, Emmett and Teller (BET) specific surface area, and/or a high electrical conductivity. Methods are provided to produce the nanoparticles and agglomerates at a high production rate without using catalysts.

Provided is method for synthesising core-shell nanoparticles by laser pyrolysis. The method may include a) conveying together a gaseous mixture including a silicon precursor and a germanium precursor in a reaction zone of a first chamber of a reactor, and b) emitting a first laser beam at the level of the reaction zone for carrying out a laser pyrolysis of the mixture, the steps making it possible to obtain nanoparticles having a core made of a silicon- and germanium-based alloy and a silicon shell.

A method for fabricating an infiltrated object of a desired shape having a high volume fraction of infiltrant using an additively manufactured preform. Using an additive manufacturing technique, the preform is formed with graded macro-porosity. When infiltrated, the void volume of the macro-porosity is filled with infiltrant Optionally, the void volume may be varied across the profile of the object to create a gradient of mechanical properties in the infiltrated object.

A method for fabricating an infiltrated object of a desired shape having a high volume fraction of infiltrant using an additively manufactured preform. Using an additive manufacturing technique, the preform is formed with graded macro-porosity. When infiltrated, the void volume of the macro-porosity is filled with infiltrant Optionally, the void volume may be varied across the profile of the object to create a gradient of mechanical properties in the infiltrated object.

A cemented carbide includes second hard phase grains, wherein the second hard phase grains includes a core portion, and in a case where a total of 70 unit regions that are each constituted of a square having each side of 8μm are provided by successively arranging 7 unit regions in a longitudinal direction and 10 unit regions in a lateral direction in an electron microscope image of any cross section of the cemented carbide captured at a magnification of 1500×, where the total number of core portions in the total of 70 unit regions is calculated, and where a percentage of the number of core portions in each of the unit regions with respect to the total number of core portions is calculated, the number of unit regions in which the percentage is less than 0.43% or more than 2.43% is less than or equal to 10.

A cemented carbide includes second hard phase grains, wherein the second hard phase grains includes a core portion, and in a case where a total of 70 unit regions that are each constituted of a square having each side of 8μm are provided by successively arranging 7 unit regions in a longitudinal direction and 10 unit regions in a lateral direction in an electron microscope image of any cross section of the cemented carbide captured at a magnification of 1500×, where the total number of core portions in the total of 70 unit regions is calculated, and where a percentage of the number of core portions in each of the unit regions with respect to the total number of core portions is calculated, the number of unit regions in which the percentage is less than 0.43% or more than 2.43% is less than or equal to 10.

Aluminum-based metallic powders, along with their methods of production and formation, are provided. The Al-based metallic powders are formed with an increased amount of oxygen within at least a portion of the particles of the powder. The Al-based metallic powders show improved flowability.