Nanocrystalline metal powders comprising tungsten, molybdenum, rhenium and/or niobium can be synthesized using a combustion reaction. Methods for synthesizing the nanocrystalline metal powders are characterized by forming a combustion synthesis solution by dissolving in water an oxidizer, a fuel, and a base-soluble, ammonium precursor of tungsten, molybdenum, rhenium, or niobium in amounts that yield a stoichiometric burn when combusted. The combustion synthesis solution is then heated to a temperature sufficient to substantially remove water and to initiate a self-sustaining combustion reaction. The resulting powder can be subsequently reduced to metal form by heating in a reducing gas environment.

The present disclosure relates to new materials comprising Al, Ti, and Zr. The new materials may realize a single phase field of a hexagonal close-packed (hcp) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1240° C. The new materials may include 29.0-42.4 wt. % Al, 41.2-59.9 wt. % Ti, and 10.3-24.1 wt. % Zr. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.0 phase, the Al.sub.2Zr phase, and combinations thereof. The new alloys may realize improved high temperature properties.

A shaped charge liner may include an apex portion and a skirt portion extending from the apex portion. The skirt portion may include a body connected to the apex portion, a perimeter spaced apart from the apex portion, and a carbide layer extending between and spaced apart from the perimeter and the apex portion. A shaped charge for creating a perforation hole in a wellbore casing may include a shaped charge liner having at least one material having hardness that is greater than a corresponding hardness of the wellbore casing. The at least one material is configured to bond to at least one of an outer surface and an inner surface of the perforation hole upon detonation of the shaped charge and penetration of the casing by a perforation jet.

A Ta-Nb alloy powder which has provides a capacitor having a higher capacitance than a Ta capacitor and a better thermal stability in terms of an oxide film is better than a Nb capacitor, the Ta-Nb alloy powder being a Ta-Nb alloy powder produced by a thermal CVD method, wherein a content of Nb is 1 to 50 mass %, and an average particle diameter of primary particles is 30 to 200 nm, preferably, a CV value per unit mass of the powder (μF.Math.V/g) is 250 kμF.Math.V/g or more, or further, a CV value per unit volume (μF.Math.V/mm.sup.3) in terms of a molded body whose molding density ρ (g/cm.sup.3) is ρ.sub.c (g/cm.sup.3)=−0.012R.sub.Nb+3.57, wherein R.sub.Nb: Nb content (mass %) in an alloy, is 900 μF.Math.V/mm.sup.3 or more, and an anode element for a solid electrolytic capacitor using the alloy powder.

The invention relates to a method for preparing high-melting-point metal powder through multi-stage deep reduction, and belongs to the technical field of preparation of powder. The method includes the following steps of mixing dried high-melting-point metal oxide powder with magnesium powder and performing a self-propagating reaction, placing an intermediate product into a closed reaction kettle, leaching the intermediate product with hydrochloric acid as a leaching solution so as to obtain a low-valence oxide Me.sub.xO precursor of the low-valence high-melting-point metal; uniformly mixing the precursor with calcium powder, pressing the mixture, placing the pressed mixture into a vacuum reduction furnace, heating the vacuum reduction furnace to 700-1200° C., performing deep reduction for 1-6 h, leaching a deep reduction product with hydrochloric acid as a leaching solution and performing treatment, so as to obtain the high-melting-point metal powder.

A process for producing an electrode material by infiltrating a highly conductive metal such as Cu into a porous object containing heat-resistant elements. Before an infiltration step in which the highly conductive metal is infiltrated, a HIP treatment is given to a powder containing the heat-resistant elements (or to a molded object obtained by molding a powder containing the heat-resistant elements). The composition is controlled so that the HIP treatment yields a porous object which has a degree of filling of 70% or higher, more preferably 75% or higher. The highly conductive metal is infiltrated into the porous object having the controlled composition.

The present invention relates to a composite tantalum powder and a process for preparing the same, and to a capacitor anode prepared from the tantalum powder. The method for preparing a composite tantalum powder comprises the following steps of: 1) providing a tantalum powder prepared by a reduction process, and flattening the tantalum powder so as to prepare a flaked tantalum powder; 2) providing a granular tantalum powder prepared from tantalum ingot; 3) mixing the flaked tantalum powder and the granular tantalum powder to give a tantalum powder mixture; and 4) thermally treating the tantalum powder mixture, and then pulverizing, screening to give a composite tantalum powder. The present invention further relates to a composite tantalum powder prepared from the process and the use thereof in a capacitor.

This invention relates to a preparation method of rare earth oxide dispersion strengthened fee grain tungsten materials, the mass percent of the rare earth oxide is of 0.1-2%, and the rest ingredient is W. Weigh soluble rare earth salt and tungstate, dissolve into water to made into 50-100 g/L of rare earth salt solution and 150-300 g/L of tungstate solution, respectively. Firstly, add trace alkali in rare earth salt solution to control pH in 7-8, then add organic dispersant and stir to form evenly suspended R(OH).sub.3 particle colloid (R refers to rare earth element). Secondly pour the tungstate solution into the R(OH).sub.3colloid, add trace acid to control pH in 6-7, then add organic dispersant and stir to form tungstic acid micro particles, which wrap around the colloidal particles, forming coprecipitation coating particle colloid. Thirdly, the coprecipitation coating particle colloidal is spray-dried, forming tungsten and rare earth oxide compound precursor powder. Alter that, ultrafine or nanoscale tungsten powder with particle size of 50˜500 nm is obtained through a process of calcination subsequent with hydrogen thermal reduction. Finally, the tungsten powder is subjected to ordinary compression molding and then conventional high temperature sintering. The trace rare earth oxide dispersion strengthened high performance fine grain tungsten materials prepared by this invention, its density is close to full density (98.5% or higher), its grain size is uniform and very fine (average in 5˜10 microns), and the rare earth oxides particles evenly distribute in tungsten intracrystalline or grain, boundary with particle size of 100˜500 nm.

The invention relates to the rare metal smelting field, and particularly, the present invention relates to a tantalum powder for preparing capacitors and a process for preparing the tantalum powder, and to a sintered anode prepared from the tantalum powder. As to the tantalum powder as provided by the invention, its primary tantalum powder has a BET of from 3.0 to 4.5 m.sup.2/g. After the secondary agglomeration, the tantalum powder has a large particle size. The tantalum powder has an average Fisher sub-sieve size (FSSS) of 1.2 to 3.0 μm wherein as measured with a standard sieve mesh, more than 75% of tantalum powder has a +325-mesh, and a particle size distribution D50 of more than 60 μm, that is, the secondary particle size is high. A resultant capacitor anode prepared by sintering the tantalum powder of the invention at 1200° C. for 20 minutes and then being energized at the voltage of 20 V has the specific capacitance of from 140,000 to 180,000 μFV/g and the residual current of less than 1.0 nA/μFV. Meantime, the invention provides an economical process for making the tantalum powder.

A method for forming a metallization structure is provided, including forming a metallic powder layer on a substrate; performing a first laser sintering on a first portion of the metallic powder layer to form a metal layer; and in the presence of oxygen, performing a second laser sintering on a second portion of the metallic powder layer to form a metal oxide layer to serve as a first dielectric layer.