Abstract: In various embodiments, protective layers are bonded to a steel layer and connected by a layer of unmelted metal powder produced by cold spray.

Abstract: In various embodiments, a metallic structure includes first and second clad structures each comprising a protective layer disposed over a steel layer, a joint joining the steel layers of first and second clad structures, and, directly connecting the protective layers of the first and second clad structures, a layer of metal powder disposed in contact with (i) the joint, (ii) the protective layers of the first and second clad structures, and (iii) a portion of at least one of the steel layers proximate the joint.

Abstract: In various embodiments, a metallic structure includes first and second clad structures each comprising a protective layer disposed over a steel layer, a joint joining the steel layers of first and second clad structures, and, directly connecting the protective layers of the first and second clad structures, a layer of metal powder disposed in contact with (i) the joint, (ii) the protective layers of the first and second clad structures, and (iii) a portion of at least one of the steel layers proximate the joint.

Abstract: In various embodiments, a method of joining clad structures includes providing first and second clad structures each comprising a protective layer disposed only partially over a steel layer such that an edge region of the steel layer is exposed, joining the first and second clad structures at their respective edge regions, thereby forming a joint, and cold spraying a metal powder over and in contact with (i) the joint, (ii) the edge regions, and (iii) the protective layers of the first and second clad structures, thereby directly connecting the protective layers of the first and second clad structures with a layer of unmelted metal powder.

Abstract: The present invention is directed to a process for joining tantalum clad steel structures. The process broadly comprises: a) providing a first tantalum clad section, said first tantalum clad section comprising a tantalum layer over a steel layer, with a bonding layer optionally therebetween, with a portion of said steel layer in an edge region not being covered by said tantalum layer or said bonding layer, b) providing a second tantalum clad section, said second tantalum clad section comprising a tantalum layer over a. steel layer, with a bonding layer optionally therebetween, with a portion of said steel layer in an edge region not being covered by said tantalum layer or said bonding layer, c) locating said steel edge regions adjacent each other, d) welding the steel edge regions together, e) cold spraying a tantalum powder onto the welded edge regions and over the tantalum layers adjacent said edge regions thereby joining the tantalum clad steel sections.

Abstract: Process and apparatus are provided for a high energy efficiency chemical combustion process. The process provides two reaction steps, both of which are exothermic. First, a reduced oxygen carrier is contacted with oxygen in a reactor to form an oxidized oxygen carrier, such as metal oxide or metal suboxide, and then the oxidized oxygen carrier is fed to a second reactor and combusted with a fuel. The reaction produces the reduced oxygen carrier and carbon dioxide. The reduced oxygen carrier from the second reactor is recycled back to said first reactor. Carbon monoxide can also be produced during the process depending on stoichiometric amounts of the reactants. Though the process can be performed in various types of reactor systems, one preferred embodiment is the flash furnace with the production of fly ash during combustion. The process is highly efficient and produces a large amount of usable work.

Abstract: The present invention is directed to a process for the preparation of a metal powder having a purity at least as high as the starting powder and having an oxygen content of 10 ppm or less comprising heating said metal powder containing oxygen in the form of an oxide, with the total oxygen content being from 50 to 3000 ppmf in an inert atmosphere at a pressure of from 1 bar to 10?7 to a temperature at which the oxide of the metal powder becomes thermodynamically unstable and removing the resulting oxygen via volatilization. The metal powder is preferably selected from the group consisting of tantalum, niobium, molybdenum, hafnium, zirconium, titanium, vanadium, rhenium and tungsten. The invention also relates to the powders produced by the process and the use of such powders in a cold spray process.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: Refractory metal powders are dehydrided in a device which includes a preheat chamber for retaining the metal powder fully heated in a hot zone to allow diffusion of hydrogen out of the powder. The powder is cooled in a cooling chamber for a residence time sufficiently short to prevent re-absorbtion of the hydrogen by the powder. The powder is consolidated by impact on a substrate at the exit of the cooling chamber to build a deposit in solid dense form on the substrate.

Abstract: The present invention is directed to a process for joining tantalum clad steel structures. The process broadly comprises: a) providing a first tantalum clad section, said first tantalum clad section comprising a tantalum layer over a steel layer, with a bonding layer optionally therebetween, with a portion of said steel layer in an edge region not being covered by said tantalum layer or said bonding layer, b) providing a second tantalum clad section, said second tantalum clad section comprising a tantalum layer over a steel layer, with a bonding layer optionally therebetween, with a portion of said steel layer in an edge region not being covered by said tantalum layer or said bonding layer, c) locating said steel edge regions adjacent each other, d) welding the steel edge regions together, e) cold spraying a tantalum powder onto the welded edge regions and over the tantalum layers adjacent said edge regions thereby joining the tantalum clad steel sections.

Abstract: A method of producing a refractory metal powder that includes providing a metal powder containing magnesium tantalate or magnesium niobate; and heating the powder in an inert atmosphere in the presence of magnesium, calcium and/or aluminum to a temperature sufficient to remove magnesium tantalate or magnesium niobate from the powder and/or heating the powder under vacuum to a temperature sufficient to remove magnesium tantalate or magnesium niobate from the powder, the heating steps being performed in any order. The metal powder can be formed into pellets at an appropriate sintering temperature, which can be formed into electrolytic capacitors.

Abstract: The present invention is directed to a process for the preparation of a metal powder having a purity at least as high as the starting powder and having an oxygen content of 10 ppm or less comprising heating said metal powder containing oxygen in the form of an oxide, with the total oxygen content being from 50 to 3000 ppm, in an inert atmosphere at a pressure of from 1 bar to 10?7 to a temperature at which the oxide of the metal powder becomes thermodynamically unstable and removing the resulting oxygen via volatilization. The metal powder is preferably selected from the group consisting of tantalum, niobium, molybdenum, hafnium, zirconium, titanium, vanadium, rhenium and tungsten. The invention also relates to the powders produced by the process and the use of such powders in a cold spray process.

Abstract: The present invention is directed to an improved process for manufacturing a rotary anode for an x-ray tube, said rotary anode comprising a molybdenum support member on which a target layer consisting essentially of tungsten or a tungsten-rhenium alloy is provided by plasma spraying, the improvement comprising: a) preheating the support member to a temperature of from 1150° C. to 1600° C., b) placing the support member in a gaseous atmosphere containing hydrogen and having a pressure of from 0.5 to 0.9 bars and wherein hydrogen is present in a molar ratio of hydrogen to tungsten dioxide of from 5:1 to 50:1, and c) plasma spraying the target layer onto the support layer in said gaseous atmosphere. The invention is also directed to the anode produced by the process.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: Metal powder Ta and/or Nb, with or without one or metals from the group Ta, Nb, Ti, Mo, W, V, Zr and Hf, is made in a fine powder form by reduction of metal oxide by contact with a gaseous reducing agent, preferably an alkaline earth metal, to near complete reduction, leaching, further deoxidation and agglomeration, the powder so produced being sinterable to capacitor anode form and processable to other usages.

Abstract: High purity refractory metals, valve metals, refractory metal oxides, valve metal oxides, or alloys thereof suitable for a variety of electrical, optical and mill product/fabricated parts usages are produced from their respective oxides by metalothermic reduction of a solid or liquid form of such oxide using a reducing agent that establishes (after ignition) a highly exothermic reaction, the reaction preferably taking place in a continuously or step-wise moving oxide such as gravity fall with metal retrievable at the bottom and an oxide of the reducing agent being removable as a gas or in other convenient form and unreacted reducing agent derivatives being removable by leaching or like process.

Abstract: Tantalum scrap of high oxygen content is recovered and processed to metallurgical grade tantalum by fine participation. Blending with carbon or other appropriate solid reducing agent, melting in a plasma furnace (20) at about tantalum melt temperature while suppressing partial pressure of tantalum oxide gas to minimize tantalum loss of the process.

Abstract: Metal powder from the group Ta, Nb, Ti, Mo, W, V, Zr, Hf preferrably Ta or Nb, is made in a fine powder form by reduction of metal oxide by contact with a gaseous reducing agent, preferrably an alkaline earth metal, to near complete reduction, leaching, further deoxidation and agglomeration, the powder so produced being sinterable to capacitor anode form and processable to other usages.