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Influence of air pressure on erosion of anode and cathode arcs
Classified
abstracts
926440
vapour can be used for production of negative hydrogen ion beams. B A Dyachkov et al, Zh T&h Fiz, 41 (ll), Nov 1971, 2353-2356 (in Russian.) 37. METALLURGY, CHEMISTRY
INORGANIC
CHEMISTRY,
ANALYTICAL 37
926. Form of the crystallization
front in crucible-less
zone melting.
(USSR)
An inductor is described which provides stable liquid zones in the zone melting of alloys in vacuum and inert gas atmosphere. The forms of crystallization fronts with various inductor shapes and sample cooling modes are investigated. Ch V Kopetskiy and V A Marchenko, Prib Tekh Eksper, No 5, 1971, 231-233 (in Russian). 31 927. Equipment for ion implantation. (USSR) A simple ion gun without a mass separator is described which can be mounted in any apparatus for vacuum evaporation. The gun is intended for the preparation of thin (< 1 pm) highly doped regions in semiconductors. At high doping levels purification of the ion beam by the method of magnetic separation is not required. G A Kachurin, Prib Tekh Eksper, No 5, 1971, 222-223 (in Russian). 37 928. Determination of absolute concentration of zinc atoms in gaseous phase by an atomic absorption method. (USSR) An atomic absorption technique is used to determine the absolute concentration of zinc atoms in the gaseous phase, in the temperature range of 571 to 717”K, using an absorption cell processed at pressure of 5 x 1O-8 torr and sealed at 1 x 1O-5torr. 0 N Muradova and V G Muradov, Zzv VUZ Fiz, No 12, 1971, 123125 (in Russian). 37 929. Oxidation rate of WSe,. (USSR) Kinetics of oxidation of dense WSe, samples is investigated in the temperature range of 300 to 800°C. The formation of lower oxides in secondary reactions between WSe, and WO, is explored in vacuum at 1O-2 torr. A N Zelikman et al, Neorg Muter, 7 (1 l), 1971,1942-1946 (in Russian). 37 930. Determination of gases in ferrous alloys containing silicon. (USSR) It is recommended that the determination of gas contents in ferrous alloys containing silicon be performed by vacuum melting in a nickel bath with additions of cerium and tin. V S Shitikov and V P Sergienko, Zavodsk Lab, 37 (12), 1971, 14201421 (in Russian). 37 931. Application of activated magnesium in the quantitative microdetermination of hydrogen in organic materials. (USSR) A volumetric method of determining the hydrogen content of organic materials is presented, which is based on thermal decomposition of the analyzed material in a closed evacuated tube, in the presence of powdered magnesium activated by iodine. P N Fedoseev and G 0 Baydulina, Zuvodsk Lab, 37 (12), 1971, 1424 1425 (in Russinn). 37 932. Investigation of stability of solid solutions in the system ZrO,Ln,O,. (USSR) Stability of solid solutions in the system ZrO%-Ln,O, (Ln-rare earth element and Y) is investigated at high temperatures with the aid of an x-ray analyzer and a high-temperature dilatometer both in vacuum and in air. It is found that decomposition of solid solutions is slower in vacuum than in air. V B Glushkova et al, Neorg Mater, 7 (ll), 1971, 2007-2014 (in Russian). 37 933. Stability of oxide-carbides in the system ZrC-ZrO,. (USSR) Products of interaction of ZrC and ZrO, at 2320°K and lo-* torr are investigated. It is found that in the cases, when the partial pressure of CO in the system Zr-C-O does not correspond to the equilibrium partial pressure of CO, the ternary phases of variable composition ZrC,O, and probably other oxide-carbides are not thermodynamically stable. V M Gropyanov et al, Neorg Mater, 8 (l), 1972,88-91 (in Russian). 294
934. Structure of a material titanium. (USSR)
based
on silicon
carbide
alloyed
37 with
The structure of a material based on silicon carbide alloyed with titanium for increasing its resistance against erosion, is investigated in a high-temperature microscope in vacuum at low5 torr and temperatures up to 1400°C. Experimental results are discussed. VP Samsonov et al, Neorg Mater, 7 (12), 1971,2175-2178 (in Russian). 37 935. Investigation of the induction period of crystallization of quartz glass.
(USSR)
Kinetics of crystallization of quartz glass in a vacuum furnace at 1O-4 torr and in air is investigated. Experimental results are discussed. V K Leko and L A Komarova, Neorg Muter, 7 (12), 1971, 2240-2244 (in Russian). 37 936. Thermal transformations of acid sodium tripolyphosphate Na,HP,O,,.H,O. (USSR) Dehydration of the crystallohydrate NalHP301,,.He0 is investigated in vacuum at 1O-4 torr and in a flow of water vapour at atmospheric pressure using the methods of x-ray, dispersion and chromatographic analyses. The reaction products are determined. E A Prodan et al, Neorg Muter, 8 (l), 1972,106110 (in Russian). 37 937. Experimental arrangements for high-temperature investigations of the interaction kinetics pressures. (USSR)
of construction
materials
with gases at low
Two types of system for investigating the interaction kinetics of construction materials with gases at pressures down to lo-’ torr and temperatures to 15OOC, are described. In the first system, the reaction volume, in the form of vacuum-dense alundum tube, and the external heater have automatically controlled pumping systems. In the second, an optical bi-ellipsoidal heater located in the vacuum volume is used. Both arrangements are equipped with oil-free pumps and an automatic gas admission regulator with a pressure range of 1O-s to 10-r torr. Experiments with O,, N,, CO, CH, and H,O vapour showed that it is possible to produce sufficiently pure gas ambient in the described systems. F Ya Leyn et al, Prib Tekh Eksper, No 2, 1971, 199-201 (in Russian). 37 938. Application of diffusion welding in vacuum of hard alloy to steel in the fabrication of stamped components. (USSR) The method of diffusion welding in vacuum for the bonding of metals and alloys is described. The results of an investigation of the technique for hard alloys to steel bonding in the fabrication of stamped components, are presented. Two diffusion welding systems were used with base pressures of 1 x 1O-s and 2x 1O-6 torr. Nickel powder filler was used and the optimum conditions were found to be temperature of 1lOO”C, pressure of 1.5 kg/mm2 and time of welding of 10 minutes. Results of special analysis of weld compound are presented. A method for determination of internal stresses in the weld zone is given. It is found that minimum stresses exist in samples cooled to 850°C in vacuum and then further cooled in air. N F Kazakov et al, Elektron Obrab Mufer, No 5, 1971, 60-63 (in Russian). 37 939. Influence of air pressure on erosion of anode and cathode arcs. (USSR) Influence of air pressure on erosion of anode and cathode during electric spark treatment is investigated in a vacuum chamber in the pressure range of 10-l to 760 torr. It is found that at 10-l torr the erosion action of anode arc is reduced by 10 times in comparison to atmospheric pressure operation. S Z Bakal, Elektron Obrub Mater, No 5,1971,2&21 (in Russian). 38. DISTILLATION, ANALYSIS
ORGANIC
CHEMISTRY,
ISOTOPE
GAS
38 940. Effect of mass spectrometer background on the reproducibility of isotopic analysis of nitrogen and oxygen. (USSR) A method for determining the nitrogen and oxygen concentrations while eliminating the influence of the background of the mass spectrometer, is presented. Influence of instabilities in the gas admission system and ion source operation is also evaluated. EN Vito1 et al, ZavodskLab, 37 (12), 1971, 14661469 (in Russian).
abstracts
926440
vapour can be used for production of negative hydrogen ion beams. B A Dyachkov et al, Zh T&h Fiz, 41 (ll), Nov 1971, 2353-2356 (in Russian.) 37. METALLURGY, CHEMISTRY
INORGANIC
CHEMISTRY,
ANALYTICAL 37
926. Form of the crystallization
front in crucible-less
zone melting.
(USSR)
An inductor is described which provides stable liquid zones in the zone melting of alloys in vacuum and inert gas atmosphere. The forms of crystallization fronts with various inductor shapes and sample cooling modes are investigated. Ch V Kopetskiy and V A Marchenko, Prib Tekh Eksper, No 5, 1971, 231-233 (in Russian). 31 927. Equipment for ion implantation. (USSR) A simple ion gun without a mass separator is described which can be mounted in any apparatus for vacuum evaporation. The gun is intended for the preparation of thin (< 1 pm) highly doped regions in semiconductors. At high doping levels purification of the ion beam by the method of magnetic separation is not required. G A Kachurin, Prib Tekh Eksper, No 5, 1971, 222-223 (in Russian). 37 928. Determination of absolute concentration of zinc atoms in gaseous phase by an atomic absorption method. (USSR) An atomic absorption technique is used to determine the absolute concentration of zinc atoms in the gaseous phase, in the temperature range of 571 to 717”K, using an absorption cell processed at pressure of 5 x 1O-8 torr and sealed at 1 x 1O-5torr. 0 N Muradova and V G Muradov, Zzv VUZ Fiz, No 12, 1971, 123125 (in Russian). 37 929. Oxidation rate of WSe,. (USSR) Kinetics of oxidation of dense WSe, samples is investigated in the temperature range of 300 to 800°C. The formation of lower oxides in secondary reactions between WSe, and WO, is explored in vacuum at 1O-2 torr. A N Zelikman et al, Neorg Muter, 7 (1 l), 1971,1942-1946 (in Russian). 37 930. Determination of gases in ferrous alloys containing silicon. (USSR) It is recommended that the determination of gas contents in ferrous alloys containing silicon be performed by vacuum melting in a nickel bath with additions of cerium and tin. V S Shitikov and V P Sergienko, Zavodsk Lab, 37 (12), 1971, 14201421 (in Russian). 37 931. Application of activated magnesium in the quantitative microdetermination of hydrogen in organic materials. (USSR) A volumetric method of determining the hydrogen content of organic materials is presented, which is based on thermal decomposition of the analyzed material in a closed evacuated tube, in the presence of powdered magnesium activated by iodine. P N Fedoseev and G 0 Baydulina, Zuvodsk Lab, 37 (12), 1971, 1424 1425 (in Russinn). 37 932. Investigation of stability of solid solutions in the system ZrO,Ln,O,. (USSR) Stability of solid solutions in the system ZrO%-Ln,O, (Ln-rare earth element and Y) is investigated at high temperatures with the aid of an x-ray analyzer and a high-temperature dilatometer both in vacuum and in air. It is found that decomposition of solid solutions is slower in vacuum than in air. V B Glushkova et al, Neorg Mater, 7 (ll), 1971, 2007-2014 (in Russian). 37 933. Stability of oxide-carbides in the system ZrC-ZrO,. (USSR) Products of interaction of ZrC and ZrO, at 2320°K and lo-* torr are investigated. It is found that in the cases, when the partial pressure of CO in the system Zr-C-O does not correspond to the equilibrium partial pressure of CO, the ternary phases of variable composition ZrC,O, and probably other oxide-carbides are not thermodynamically stable. V M Gropyanov et al, Neorg Mater, 8 (l), 1972,88-91 (in Russian). 294
934. Structure of a material titanium. (USSR)
based
on silicon
carbide
alloyed
37 with
The structure of a material based on silicon carbide alloyed with titanium for increasing its resistance against erosion, is investigated in a high-temperature microscope in vacuum at low5 torr and temperatures up to 1400°C. Experimental results are discussed. VP Samsonov et al, Neorg Mater, 7 (12), 1971,2175-2178 (in Russian). 37 935. Investigation of the induction period of crystallization of quartz glass.
(USSR)
Kinetics of crystallization of quartz glass in a vacuum furnace at 1O-4 torr and in air is investigated. Experimental results are discussed. V K Leko and L A Komarova, Neorg Muter, 7 (12), 1971, 2240-2244 (in Russian). 37 936. Thermal transformations of acid sodium tripolyphosphate Na,HP,O,,.H,O. (USSR) Dehydration of the crystallohydrate NalHP301,,.He0 is investigated in vacuum at 1O-4 torr and in a flow of water vapour at atmospheric pressure using the methods of x-ray, dispersion and chromatographic analyses. The reaction products are determined. E A Prodan et al, Neorg Muter, 8 (l), 1972,106110 (in Russian). 37 937. Experimental arrangements for high-temperature investigations of the interaction kinetics pressures. (USSR)
of construction
materials
with gases at low
Two types of system for investigating the interaction kinetics of construction materials with gases at pressures down to lo-’ torr and temperatures to 15OOC, are described. In the first system, the reaction volume, in the form of vacuum-dense alundum tube, and the external heater have automatically controlled pumping systems. In the second, an optical bi-ellipsoidal heater located in the vacuum volume is used. Both arrangements are equipped with oil-free pumps and an automatic gas admission regulator with a pressure range of 1O-s to 10-r torr. Experiments with O,, N,, CO, CH, and H,O vapour showed that it is possible to produce sufficiently pure gas ambient in the described systems. F Ya Leyn et al, Prib Tekh Eksper, No 2, 1971, 199-201 (in Russian). 37 938. Application of diffusion welding in vacuum of hard alloy to steel in the fabrication of stamped components. (USSR) The method of diffusion welding in vacuum for the bonding of metals and alloys is described. The results of an investigation of the technique for hard alloys to steel bonding in the fabrication of stamped components, are presented. Two diffusion welding systems were used with base pressures of 1 x 1O-s and 2x 1O-6 torr. Nickel powder filler was used and the optimum conditions were found to be temperature of 1lOO”C, pressure of 1.5 kg/mm2 and time of welding of 10 minutes. Results of special analysis of weld compound are presented. A method for determination of internal stresses in the weld zone is given. It is found that minimum stresses exist in samples cooled to 850°C in vacuum and then further cooled in air. N F Kazakov et al, Elektron Obrab Mufer, No 5, 1971, 60-63 (in Russian). 37 939. Influence of air pressure on erosion of anode and cathode arcs. (USSR) Influence of air pressure on erosion of anode and cathode during electric spark treatment is investigated in a vacuum chamber in the pressure range of 10-l to 760 torr. It is found that at 10-l torr the erosion action of anode arc is reduced by 10 times in comparison to atmospheric pressure operation. S Z Bakal, Elektron Obrub Mater, No 5,1971,2&21 (in Russian). 38. DISTILLATION, ANALYSIS
ORGANIC
CHEMISTRY,
ISOTOPE
GAS
38 940. Effect of mass spectrometer background on the reproducibility of isotopic analysis of nitrogen and oxygen. (USSR) A method for determining the nitrogen and oxygen concentrations while eliminating the influence of the background of the mass spectrometer, is presented. Influence of instabilities in the gas admission system and ion source operation is also evaluated. EN Vito1 et al, ZavodskLab, 37 (12), 1971, 14661469 (in Russian).