摘要:
A sintered rhenium crucible, highly suitable for growing single crystals from refractory metal oxides, for example by the Czochralski technique, is formed of fine rhenium powder, by sintering. A compact is formed by cold isostatic pressing and thereafter the compact is sintered at 500-2800.degree. C. to obtain a sintered crucible. Product density is limited to 88-95% of theroretical in order to maximize creep resistance.
摘要:
A method of manufacturing an electrically conductive cermet that includes less than 35% by volume of a precious metal by mixing a powdered refractory ceramic with the powdered metal, molding the mixture into a green, and sintering the green to create a cermet with a dense ceramic phase and a metallic phase in the form of a coherent network. The object is good electric conductivity at a low metal content. The precious metal powder is selected to shrink less and exhibits less sintering tendency as it forms the metallic phase than does the ceramic powder as it forms the ceramic phase.
摘要:
A process for making a crystalline solid-solution powder which involves reacting at least two reactants in a plasma arc of a plasma chamber and blast-cooling the resultant product in a high velocity gas stream to form the powder. The first reactant is a molten metal alloy and the second reactant is a gas. The reaction is carried out in a plasma arc and the products rapidly cooled by a gas stream acting at the outlet opening of the plasma chamber. The crystalline solid-solution powder formed by the process has a low electrical resistivity. If an indium-tin alloy is used as the first reactant and oxygen as the second reactant, there is obtained an indium-tin-oxide (ITO) crystalline solid-solution powder which, when compacted to 40% of its theoretical density, has an electrical resistivity in the range of about 2 .OMEGA.cm. This ITO crystalline solid-solution powder is particularly suitable for preparing an ITO target, with high electrical conductivity and thus high achievable sputtering rates.
摘要:
The targets for cathodic sputtering according to this invention are formed of hot-pressed or hot isostatic-pressed indium oxide/tin oxide powder with a minimum density of 95% of the theoretical density and with a sub-stoichiometric oxygen content are known. In order to provide the improvement of high stability and, simultaneously, high sputtering rate, it is proposed according to the invention that the target have a crystalline phase which is formed as a solid solution of indium oxide and tin oxide with a minimum of 90% by weight, preferably a minimum of 97%, of the solid solution, and which has an average grain size ranging from 2 .mu.m to 20 .mu.m. In order to make available a simple and cost-efficient method for producing a target consisting of a starting powder of indium oxide/tin oxide, which allows for a precise setting of the oxygen content and a homogeneous chemical composition throughout the entire target volume, it is proposed that a starting powder be used that is produced by oxidizing finely distributed indium tin metal.
摘要:
A component made of sintered oxides of indium and tin and a method of manufacturing such a component. The mean size of the oxide particles is larger than 2 .mu.m. The empirical density of the component is more than 95% of theoretical. The component is characterized in that at least 97 weight % of the oxide particles are solid solution crystals with a crystalline matrix of indium oxide. The method comprises molding a green body of a powder of indium-oxide and tin-oxide solid solution and sintering the green body at a temperature less than 1100.degree. C. and preferably between 800.degree. and 1050.degree. C.
摘要:
A method is provided for producing a wire or tape, especially for use as an electrode or electrode tip in spark plugs. The method includes the following steps: (a) producing an intermetallic compound having a melting point above 1700° C.; (b) grinding the intermetallic compound; (c) mixing the intermetallic compound with metal powder; (d) introducing the mixture obtained in step (c) in a tube produced from ductile material; and (e) shaping the tube filled in step (d) to give a wire or tape. Also provided are a wrapped wire or wrapped tape, especially a semifinished product for producing electrodes or electrode tips of spark plugs.
摘要:
The invention relates to a metal component for discharge lamps, having a support of niobium or tantalum or of alloys based on niobium and/or tantalum, as well as a discharge lamp. The present invention is addressed to the problem of increasing the resistance to oxidation and corrosion of metal components having a support of niobium or tantalum or of alloys based on niobium and/or tantalum which are disposed in or on discharge lamps. The problem is solved according to the invention in that the support has a coating of one or more single layers which is formed of at least one noble metal and/or from a noble metal alloy.
摘要:
Fine-mesh warp-knit fabrics of noble metal-containing wires with high specific surface areas, having good mechanical stability, are produced by warp-knitting noble metal-containing wires to form closed stitches, such that the warp-knit fabric has at least 14 stitches per inch, and such that in at least one of the knit weaves forming the warp-knit fabric, the noble metal-containing wires are laid down over at least three stitch spacings.
摘要:
The addition of 0.5 to 30 ppm boron and 0.5 to 20 ppm calcium to iridium and the Zr- and Hf-free alloys thereof and rhodium and the Zr- and Hf-free alloys thereof surprisingly increases the creep rupture strength at high temperatures, in particular around 1,800° C.
摘要:
A metal fiber based on one or several elements from the group of platinum, palladium, rhodium, ruthenium, and iridium with 0 to 30% by weight of one or several additional alloy elements from the group of nickel, cobalt, gold, rhenium, molybdenum, and tungsten, contains 1 to 500 ppm by weight of boron or phosphorus. A non-woven material or netting, in particular for the production of nitrogen oxide or for the production of hydrocyanic acid, is made of such fibers. For the production of fibers based on noble metals having up to 30% by weight of additional alloy metals by drawing the fibers from a melt, the melting point of the metal is reduced by at least 400 ° C., before drawing of the fibers, by additionally alloying with boron or phosphorus, and the boron or the phosphorus is removed again from the fibers.