Abstract: A silicide-based composite toughened with a niobium-based metallic phase and further containing a silicon-modified chromium-based Laves-type phase to promote oxidation resistance. The silicide-based composite generally contains one or more silicide intermetallic phases, each of which is an M.sub.5 Si.sub.3 -type or an M.sub.3 Si-type phase where M is at least Nb+Ti+Hf. The niobium-based metallic phase contains at least niobium, titanium, hafnium, chromium, aluminum and silicon. The silicon-modified Laves-type phase is of the Cr.sub.2 M type where M is Nb+Ti+Hf. The silicide-based composite is formulated to contain greater than 25 volume percent of the niobium-based metallic phase, the balance being the silicide intermetallic phases and the silicon-modified Laves-type phase.

Abstract: A silicide-based composite toughened with a niobium-based metallic phase, and further containing a phase that significantly improves the oxidation resistance of the composite. The oxidation-resistant phase is a chromium-based Laves-type phase modified with silicon, which has been shown to greatly increase the oxidation resistance of silicide-based composites at temperatures of up to 1200 C. The oxidation-resistant silicide-based composite generally contains one or more silicide intermetallic phases, each of which is an M.sub.5 Si.sub.3 -type phase where M is Nb+Ti+Hf. The niobium-based metallic phase contains niobium, titanium, hafnium, chromium, aluminum and silicon. The silicon-modified Laves-type phase is of the Cr.sub.2 M type where M is Nb+Ti+Hf. A silicide-based composite contains, in atomic percent, about 12-25% titanium, about 6-12% hafnium, about 15-25% chromium, about 1-8% aluminum and about 12-20% silicon, with the balance essentially niobium.

Abstract: Nb-base alloys that include Ti, Hf, Cr, Al and Si as alloy constituents have a microstructure that includes a metallic solid solution phase and a mixture of intermetallic silicide phases. The metal silicide phases include an M.sub.3 Si silicide, where M comprises Nb, Ti or Hf, and an M.sub.5 (Si, Al).sub.3 silicide, where M comprises Nb, Ti or Hf. These alloys have mechanical properties such as low temperature fracture toughness, high temperature fracture strength, high temperature stress rupture strength and high temperature creep resistance, that meet or exceed those of certain Ni-base superalloys.

Abstract: High temperature melting niobium-titanium-chromium-aluminum-silicon alloys having a wide range of desirable microstructures, excellent microstructural and morphological properties, superior oxidation resistance at temperatures from 1000.degree. C. to 1500.degree. C., and good low temperature toughness and good high temperature strength and creep resistance are described which comprise generally two- or three-or four-phase alloys systems having compositions (31-41)Nb-(26-34)Ti-(8-10)Cr-(6-12)Al-(9-18)Si. Two-phase beta+Nb.sub.5 Si.sub.3 -base alloys can be obtained by increasing the Nb/Ti ratio, while three-phase beta+Nb.sub.5 Si.sub.3 -base+Ti.sub.5 Si.sub.3 -base alloys or four-phase beta+Nb.sub.5 Si.sub.3 -base+Ti.sub.5 Si.sub.3 -base +Ti.sub.3 Si-base alloys can be obtained by decreasing the Nb/Ti ratio.

Abstract: An amorphous alloy which is resistant to hot corrosion in sulfidizing and oxidizing atmospheres at high temperatures, consisting of at least one element selected from the group of Al and Cr and at least one element selected from the refractory metals Mo, W, Nb, and Ta, a portion of the set forth refractory metals being allowed to be substituted with at least one element selected from Fe, Co, Ni and Cu. The addition of Si further improves the alloy's oxidation resistance.

Abstract: Tantalum-based and niobium-based alloys made up entirely of a crystalline medium exhibiting a substantially continuous centered cubic structure, comprising an intermetallic compound of formula Ti.sub.2 AlMo, and having the following compositions on an atomic basis:______________________________________ Ta + Cr 20 to 35% Cr 0 to 5% Ti 20 to 40% Al 8 to 20% Mo 8 to 20%, ______________________________________wherein the concentration of Ta is less than 30%; and ______________________________________ Nb + Cr 20 to 60% Cr 0 to 5% Ti 20 to 40% Al 8 to 20% Mo 8 to 20%. ______________________________________ .

Abstract: A dental alloy is provided which is free of palladium, gallium and copper and which is compatible with a wide variety of composites and porcelain compositions. The alloy has a melting range of between about 870.degree. C. and 1230.degree. C. and a coefficient of thermal expansion of between 15.5.times.10.sup.-6 and 17.5.times.10.sup.-6 in/in/.degree. C. when heated from room temperature to 500.degree. C. The alloy contains between about 40 and 80 percent by weight gold, between 5 and 50 percent by weight of thermal expansion adjuster, between two and 15 percent by weight strengthener and oxide former, up to about 1.5 percent by weight grain refiner, and up to about 0.25 percent by weight deoxidizer.

Abstract: An alloy comprising at least two refractory metals having melting temperatures differing by at least 200.degree. C., and being present in proportions by weight such that solidification begins at a temperature at least 150.degree. C. less than the solidification temperature of the metal having the highest melting point. The alloy is produced by coelectrodeposition, and is in the form of conglomerates of dimensions between 0.2 and 30 mm of crystals of size 0.1 to 1 mm, in which the refractory metals are in a solid solution state.

Abstract: The alloy is preferably an alloy having a niobium and titanium base according to the expression:Nb-Ti.sub.27-40.5 -Al.sub.4.5-10.5 -Hf.sub.1.5-5.5 Cr.sub.4.5-7.9 V.sub.0-6,wherein the ratio of concentrations of Ti to Nb (Ti/Nb) is greater than or equal (.gtoreq.) to 0.5, andwherein the maximum concentration of the Hf+V+Al+Cr additives is less than or equal (.ltoreq.) to the expression:16.5+(5.times.Ti/Nb),and the minimum concentration of these additives is 10.5.The crystal form of the alloy is specifically body centered cubic crystal form.

Abstract: An erosion and corrosion resistant ferrochromium alloy comprising the following composition, in wt. %, 34-50 chromium, 1.5-2.5 carbon, up to 5 manganese, up to 5 silicon, up to 5 molybdenum, up to 10 nickel, up to 5 copper, up to 1% of each of one or more micro-alloying elements selected from the group consisting of titanium, zirconium, niobium, boron, vanadium and tungsten, and balance, iron and incidental impurities.The alloy has a microstructure comprising eutectic chromium carbides in a matrix comprising one or more of ferrite, retained austenite and martensite, as herein defined. Optionally, the microstructure further comprises one of primary chromium carbides, primary ferrite or primary austenite in the matrix.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron donor material and carbon donor material. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing a wide ranging varying volume percentage of ceramic, metal, and porosity.

Abstract: A method for improving the corrosion resistance of a zirconium-based material in an acid environment. A laser beam is scanned across the entire surface of the material to cause surface melting of the material. A rapid self-quenching is provided by the underlying substrate. Homogeneous material formed during solidification of the molten pool improves the corrosion resistance. Alloy enriched diffuse regions, i.e., tin and iron, develop parallel to each other and the periphery of the edge of the melt pool. In this manner, the laser surface melting removes the intermetalics by dissolving the precipitates, thus removing the source of localized corrosion. This greatly reduces the capability of the iron to act anodically to cause the zirconium to ionize, disassociate from the matrix, and migrate into the acid solution.

Abstract: Intermetallic compounds or alloys comprising niobium with and from 10 to 28 atomic percent titanium and from 14 to 17.5 atomic percent aluminum characterized by very high temperature melting points, high compressive strength at room temperature, higher room temperature compressive strength after annealing, machineable with conventional tooling, a B2 crystal structure in the as-cast condition, a two-phase microstructure in the annealed condition consisting of a B2 matrix and a second phase with the A15 crystal structure, an expected low value for coefficient of thermal expansion and susceptible to fabrication into single crystals.

Abstract: Improvement of Nb-alloys, which are known as heat-resistant alloys, by giving anti-oxidation property thereto and increasing the high temperature strength thereof. In addition to a determined amount of Al, one of (1) suitable amounts of Ti, Cr and V, and (2) suitable amounts of Cr and Co, are added to Nb-matrix, and a high melting temperature metal oxide such as Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 is dispersed in the matrix. Preferable method of preparing the alloys is combination of mechanical alloying and subsequent hot processing.

Abstract: A wrought metal alloy product having a tantalum or niobium base metal, 10 to 1000 ppm silicon, and 10 to 10000 ppm yttrium nitride. Fine uniform grain size contributes to improved ductility.

Abstract: A process for the manufacture of dispersion-strengthened alloys of the refractory metals of the 4th, 5th and 6th subgroups of the Periodic Table for application in semi-finished products or preformed parts requiring high thermal creep-resistances, involves integrating dispersion-strengthening into the process in 2-4 partial operational steps through thermal reshaping, utilizing only 3-25% strain per partial step. Annealing processes are implemented between the individual reshaping processes at temperatures, which at least during some part of the annealing process, are below the respective recrystallization temperatures of the alloy materials. The maximum deformation of the alloy materials is 75%, but is normally substantially lower. Components manufactured from the materials produced according to the process include tools used in isothermic high-temperature forging or in rotating anode X-ray tubes.

Abstract: A superalloy composition comprising niobium, an element selected from the group consisting of rhenium and technetium, and, optionally, an element selected from the lanthanide and actinide series, scandium, yttrium and lanthanum.

Abstract: Tantalum and tantalum-based alloys, particularly in wire form, are significantly improved in retention of a fine grain size at elevated temperatures and in resistance to embrittlement by the addition of 10 to 1000 ppm silicon and 10 to 1000 ppm thorium-containing material.

Abstract: A graded material system comprising: a refractory metal alloy base having a major metal selected from the group consisting of Group V-B metals (columbium, tantalum and vanadium), and having at least one alloy metal selected from the group consisting of Group IV-B metals (titanium, zirconium and hafnium), Group VI-B metals (molybdenum, tungsten and chromium) and mixtures thereof. The base has a surface containing non-metallic pick-ups in concentration of at least 1 mg/cm.sup.2 at said surface and decreasing inwardly from said surface. The non-metallic pick-ups are selected from the group consisting essentially of: oxygen and carbon; oxygen, carbon and nitrogen; oxygen, carbon and boron; and oxygen, carbon, nitrogen and boron.

Abstract: Disclosed are a group of nickel/titanium/niobium alloys wherein the niobium varies from about 2.5 to 30 atomic percent. Also disclosed is an aritcle made from these nickel/titanium/niobium alloys.

Abstract: A spinodal decomposition type ternary magnetic allioy is provided which contains, by weight, 3 to 40% vanadium, 5 to 45% chromium and the balance essentially iron. Optionally the alloy may contain at least one additional element, said additional element being present individually in an amount of 0.1 to 5% by weight and not greater than the amount of either vanadium or chromium. The alloy is easy to work and has excellent hard or semi-hard magnetic properties comparable with those of conventional iron-chromium-cobalt alloys. Yet the alloy is low in material cost and simple and inexpensive to manufacture.

Abstract: Disclosed is a novel refractory metal alloy that retains the essential characteristics of pure tantalum and, additionally, has improved engineering characteristics and may be produced at a lower cost than pure tantalum. The alloy nominally contains, by weight, about 58% tantalum, about 2.0% molybdenum, about 2.5% tungsten and about 37.5% columbium.

Abstract: Solid solutions of titanium, a second metal such as niobium, vanadium, and molybdenum and a third metal such as cobalt, germanium, or iron, wherein the second metal is niobium or vanadium and optionally when the second metal is molybdenum, react rapidly at room temperature obviating the need for a high temperature induction period. Solid solutions having formula (Ti.sub.1-x Nb.sub.x).sub.1-y M.sub.y wherein 0.25.ltoreq.x.ltoreq.0.95 and wherein y varies from at least about 0.01 to the solubility limit of M such as cobalt, germanium, or iron in said solution, are also disclosed. Hydrides of solid solution alloys of Ti/Mo/M, Ti/Nb/M and Ti/V/M are also disclosed.

Abstract: A chrome-tantalum thin film resistor having a chrome-tantalum alloy thin film containing 10 to 95 atomic % of chrome. By subjecting this chrome-tantalum alloy thin film to heat treatment at temperatures not higher than 900.degree. C., a stable resistor can be obtained. Alternatively, by forming the chrome-tantalum alloy thin film on a substrate which is preheated at temperatures not higher than 900.degree. C., the temperature coefficient of resistance of the resistor can be improved so that a stable resistor can be obtained.

Abstract: Vanadium alloys and their fabrication to produce materials for fusion applications having small additions of Ti, C and Zr that improve resistance to helium embrittlement.