- Email: [email protected]
184. Solder for joining electrical-vacuum parts
Classified abstracts 180-187 38. DISTILLATION, ORGANIC CHEMISTRY, ISOTOPE GAS ANALYSIS 38 180. Thermal decomposition of n-pentane. 1. Rate-pressure relations and survey of reaction products. (Hungary) The pyrolysis of n-pentane has been investigated at temperatures between 510 and 560°C and at initial pressures of 50-300 torr. The reaction was followed by pressure measurements and by gas chromatographic analysis. L Szirovicza et al, Acta Univ Szegediensis, Acta Phys Cbem, 17 (1/2), 1971, 33 42.
IV. Materials and techniques used in vacuum technology 41. METALS AND ALLOYS 41 181. Copper alloy refined through internal oxidation. (Hungary) A Cu-Be alloy possessing optimal properties for application in vacuum devices may be produced by internal oxidation when the Be concentration ranges from 0.10 to 0.25 per cent. The temperature of oxidation is 900°C and the period of oxidation is 4-6 h for material of 0.5 mm thickness. Internally oxidised alloys retain their strength and hardness unchanged up to a temperature of 800°C. L Egri and G Hatta, Csepeli Muszaki-Kozgazdasagi Szemle, No 2, 1971, 36-39 (in Hungarian). 45. SOLDERING, WELDING, BRAZING, SOLDERS 45 182. Solder for joining parts of electrical vacuum apparatus. (USSR) in order to reduce the soldering time and temperature involved in the joining of fine metal parts in electrical vacuum apparatus, a new type of solder containing 12-20 per cent gallium and 2-6 per cent germanium (balance/copper) is proposed. The melting range is 960990°C, and the solder runs easily over copper, steel, molybdenum, nickel, and various common alloys in a hydrogen atmosphere. Soldering may be effected within the range 980-1000°C. R E Kovalevskii et al, USSR Patent No 315549, appl 27th July 1970, pubhl 24th November 1971. 45 183. Solder fur Vacuum-tight soldering. (USSR) A new solder for vacuum-tight soldering in electrical vacuum apparatus is proposed; it differs from its predecessors in containing 0.1-2.5 per cent of nickel, the remaining components being: germanium 3-6.5, boron 0.3-1.5 per cent, balance copper. In exceptional cases the proportion of germanium may be further increased and that of boron lowered, this easing the spread of solder over the join. The proposed solder melts at 985-1015°C and flows readily over copper, kovar, and nickel; soldering generally takes place at 1000-1020°C. R E Kovalevskii et al, USSR Patent No 313632, appl 16th July 1970, publd 15th November 1971.
76
45 184. Solder for joining electrical-vacuum parts. (USSR) In order to improve the quality and strength of soldered joints between metallic and ceramic components, it is proposed to use a solder containing: nickel 17-27, iron 0.01-0.02, cobalt 0.1-0.8, silicon 0.10.6 per cent, balance copper. Up to 2.0 per cent of germanium may also be introduced in order to reduce the melting point. This solder readily wets iron, nickel, and kovar at 1160-1250°C; it only interacts slightly with the metallic component, but gives an excellent vacuumtight metal/ceramic joint. N N Tutorskaya et al, USSR Patent No 312709, appl 8th April 1970, pubhl 2nd November 197 I. 46. GLASS BLOWING, GLASS-TO-METAL AND CERAMIC-TOMETAL SEALING TECHNIQUES 46 185. Method of joining glass to parts made from a ferrochrnmium alloy. (USSR) The formation of giass/metal seals to be used in electrical vacuum apparatus is considered with special reference to the case in which the metal is an Fe-Cr alloy. An intermediate layer consisting of a metal capable of absorbing oxygen, for example, nickel, is provided. Any oxygen formed in the course of electrolytic processing is removed by this layer and the service life of the joint increases accordingly. A typical thickness of the intermediate layer is 1-5 tam. A S Levin et al, USSR Patent No 315695, appl 14th July 1969, pubM 23rd November 197 I. 47. OUTGASSING DATA, VAPOUR PRESSURE DATA, GETTERING DATA, RESIDUAL GASES IN VACUUM SYSTEMS, RESIDUAL GAS ANALYSIS 47 186. Method of determining the diffusion coefficient of gases into dielectric materials. (USSR) A simplified method of determining the diffusion coefficient of gases passing into dielectric materials of the kind used in electronic apparatus is described. The dielectric constant of the test material is measured in the absence of gas and again after gas has been allowed to pass into it to the point of saturation. Finally the dielectric constant is measured again after 20-40 per cent of the gas has been removed. By analysing the three sets of data and applying a simple equation, the diffusion coefficient may readily be calculated. E I Shul'tin and L I Linnik, USSR Patent No 315109, appl 3rdJune 1970, pubM 2nd November 1971. 47 187. Measuring the H/D ratio by compensation with type MI-1305 mass spectrometer. (Hungary) A new method is described whereby a mass spectrometer, in which the distance between the focal points for mass numbers 2 and 3 exceeds the spacing of the two ion collectors, can be employed for high-accuracy determination of H/D ratios by a compensation technique. The method is based on pulsing the accelerator voltage and a reference standard has to be used. L Matus and I Opauszky, Magyar Kern Folboirat, 77 (8), 1971, 387390 (in Hungarian).
IV. Materials and techniques used in vacuum technology 41. METALS AND ALLOYS 41 181. Copper alloy refined through internal oxidation. (Hungary) A Cu-Be alloy possessing optimal properties for application in vacuum devices may be produced by internal oxidation when the Be concentration ranges from 0.10 to 0.25 per cent. The temperature of oxidation is 900°C and the period of oxidation is 4-6 h for material of 0.5 mm thickness. Internally oxidised alloys retain their strength and hardness unchanged up to a temperature of 800°C. L Egri and G Hatta, Csepeli Muszaki-Kozgazdasagi Szemle, No 2, 1971, 36-39 (in Hungarian). 45. SOLDERING, WELDING, BRAZING, SOLDERS 45 182. Solder for joining parts of electrical vacuum apparatus. (USSR) in order to reduce the soldering time and temperature involved in the joining of fine metal parts in electrical vacuum apparatus, a new type of solder containing 12-20 per cent gallium and 2-6 per cent germanium (balance/copper) is proposed. The melting range is 960990°C, and the solder runs easily over copper, steel, molybdenum, nickel, and various common alloys in a hydrogen atmosphere. Soldering may be effected within the range 980-1000°C. R E Kovalevskii et al, USSR Patent No 315549, appl 27th July 1970, pubhl 24th November 1971. 45 183. Solder fur Vacuum-tight soldering. (USSR) A new solder for vacuum-tight soldering in electrical vacuum apparatus is proposed; it differs from its predecessors in containing 0.1-2.5 per cent of nickel, the remaining components being: germanium 3-6.5, boron 0.3-1.5 per cent, balance copper. In exceptional cases the proportion of germanium may be further increased and that of boron lowered, this easing the spread of solder over the join. The proposed solder melts at 985-1015°C and flows readily over copper, kovar, and nickel; soldering generally takes place at 1000-1020°C. R E Kovalevskii et al, USSR Patent No 313632, appl 16th July 1970, publd 15th November 1971.
76
45 184. Solder for joining electrical-vacuum parts. (USSR) In order to improve the quality and strength of soldered joints between metallic and ceramic components, it is proposed to use a solder containing: nickel 17-27, iron 0.01-0.02, cobalt 0.1-0.8, silicon 0.10.6 per cent, balance copper. Up to 2.0 per cent of germanium may also be introduced in order to reduce the melting point. This solder readily wets iron, nickel, and kovar at 1160-1250°C; it only interacts slightly with the metallic component, but gives an excellent vacuumtight metal/ceramic joint. N N Tutorskaya et al, USSR Patent No 312709, appl 8th April 1970, pubhl 2nd November 197 I. 46. GLASS BLOWING, GLASS-TO-METAL AND CERAMIC-TOMETAL SEALING TECHNIQUES 46 185. Method of joining glass to parts made from a ferrochrnmium alloy. (USSR) The formation of giass/metal seals to be used in electrical vacuum apparatus is considered with special reference to the case in which the metal is an Fe-Cr alloy. An intermediate layer consisting of a metal capable of absorbing oxygen, for example, nickel, is provided. Any oxygen formed in the course of electrolytic processing is removed by this layer and the service life of the joint increases accordingly. A typical thickness of the intermediate layer is 1-5 tam. A S Levin et al, USSR Patent No 315695, appl 14th July 1969, pubM 23rd November 197 I. 47. OUTGASSING DATA, VAPOUR PRESSURE DATA, GETTERING DATA, RESIDUAL GASES IN VACUUM SYSTEMS, RESIDUAL GAS ANALYSIS 47 186. Method of determining the diffusion coefficient of gases into dielectric materials. (USSR) A simplified method of determining the diffusion coefficient of gases passing into dielectric materials of the kind used in electronic apparatus is described. The dielectric constant of the test material is measured in the absence of gas and again after gas has been allowed to pass into it to the point of saturation. Finally the dielectric constant is measured again after 20-40 per cent of the gas has been removed. By analysing the three sets of data and applying a simple equation, the diffusion coefficient may readily be calculated. E I Shul'tin and L I Linnik, USSR Patent No 315109, appl 3rdJune 1970, pubM 2nd November 1971. 47 187. Measuring the H/D ratio by compensation with type MI-1305 mass spectrometer. (Hungary) A new method is described whereby a mass spectrometer, in which the distance between the focal points for mass numbers 2 and 3 exceeds the spacing of the two ion collectors, can be employed for high-accuracy determination of H/D ratios by a compensation technique. The method is based on pulsing the accelerator voltage and a reference standard has to be used. L Matus and I Opauszky, Magyar Kern Folboirat, 77 (8), 1971, 387390 (in Hungarian).