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Some thermophysical properties of pyrographite
Classified abstracts 112-l
23
process resulted in excessive oxidation. Atter several experiments, neither of these results was found to be instrumental in the formation I\f “L
PYFPQ&,P .,,..,I.,“.,-
.,,rfalrc= “..--..--
oxid,= .,‘.._...
Rather --...-A--)
the
hvrlrirlino ..JY”Y”‘~
w.artinn IWU”LI”II
itwlf 1.&.“11
proved to be mechanistic. The purpose of this paper is to describe experiments which will reveal that excessive oxidation is due to hydrogen reaction, suggesting a water transport mechanism recently reported by Beavis. E J Femandez and D M Holloway, J I’uc Sci Technol, 11 (3), 1974, 612-613. 37 112. Surface analysis by appearance potential spectroscopy. (Germany) The appearance-potential-spectroscopy (APS) is applied to the observation of 3 different secondary products, which are emitted of a target during electron bombardment (E = 50 . . . 1000 eV): photons, Auger-electrons and secondary-electrons. The surface-processes of the target and details of the apparatus are discussed. Some spectra are shown which yield many informations. Especially the determinations of energy thresholds, chemical shifts and band structures are possible. 31 (A\ Oh1 .“” OS4tin C:ovmnn\ \.,. --, ,,*- ,,,. , . ...__.,. AII,.) -I \ *,, 1974 _/I .) 1 _“, 1AL Khne LS.“B.,)Vnlr,,,,m_Torh 37 113. Analyses of materials with a new high current secondary ion mass spectrometer. (Germany) A secondary ion mass spectrometer has been developed and built for material- and concentration profile analysis. It consists of a Duoplasmatron Ion source with primary beam formation system, target changer, secondary ion energy selector and quadrupole mass filter. Mass resolution, dynamic range and transmission of the secondary ion analyser were investigated comparing thermal and sputter ion detection. Material analysis of several standards and samples and concentration profile measurements of implanted Cs into SIC are made by means of this apparatus. (Austria) F Pichlmayer, Vukuum-Tech, 23 (4), 1974, 98-103 (in German). 37
114. Complex investigation of thermophysical properties of refractory substances. (USSR) lll:+i. ,:... lL” - r&&,“L”L ,.nrr,.rm +r.,W.m,,t..,r:ml ,.F ..,&-..,,*,..... ““111,tt., ,,,e a,,,, rllrlll‘“&llrJ~,r~l :,.~r~nt:“n*:-.., ,‘lrr~r,~~r,“,,J “L ,r,,crcr”ly materials, apparatuses have been built for investigation of evaporation, composition and pressure of vapour, heats of evaporation reactions (sublimation, dissociation, disproportionation), enthalpy and thermal capacity, electrical resistivity, emissivity coefficients and thermal conductivity in a broad temperature interval and for determination of temperatures of melting. The apparatuses contain hightemperature high-vacuum chambers, high-temperature high-vacuum chambers with vacuum balances, mass-spectrometers modified for high-temperature investigations and calorimeters for temperature ranges of 400 to 1300” K and 1200 to 2500°K. Pressure less than 2 x 10e5 torr is achieved in the vacuum chamber for investigation of electrical conductivity of conducting refractory materials in the temperature interval of 2000 to 4000°K. In the chamber for investigation of evaporation of refractory materials in the temperature interval of 2000 to 2500°K the pressure 5 x 10m7 torr is maintained. A S Bolgar et al, Thermophys Prop of Solids, Coil, Nauka Moscow, 1077 I,,a,
115-!4! ._<
liM _._YY R,,rrinn\ \..* .-,.,.
37 115. On the character of evaporation of carbides of transition metals. (USSR) Evaporation of titanium, zironcium, hafnium and tantalum carbides is investigated in a vacuum of 1 x 10d5 torr using the Langmuir method. Evaporation of three chromium carbides is investigated using the Knudsen method. The experimental results are explained on the basis of nature of elements forming the carbides and the character of bond in these compounds. A S Bolgar, Thermophys Prop of Solids, Coil, Nauka Moscow 1973, 142-146 (in Russian). 37
Thermodynamic functions of nonstoichiometric Vanadium monocarbides at high temperatures. (USSR) Enthalpy of vanadium monocarbide with various composition in the region of homogeneity is measured in a high-vacuum high-temperature calorimeter in the temperature interval of 1300 to 2500°K. The samples of vanadium carbide were prepared by direct synthesis in a vacuum furnace at pressure 6 x 10v5 torr and temperature 1800°C. _fP^I.‘J” F,.ll IYUUI(O LT^..I._,yl”JC”W X.c^^__... *u 0 ‘P....^L^..:n, 111, “I 1Tr.““-,.-L..” r% I ul CLlalllll8X ,,rr rrr”yrryJ 1D”__ I “p “, ti”,‘“J, LLU,, 1973, 147-151 (in Russian). 116.
37 117. Evaporation of monosulphides of rare earth metals. (USSR) TTo;nn rnc.rtrr\mdrir mdhnrl with r\f t.,ntnl,.m III.LL ,.til;~ntinn ULlllrULl”., “1 IUL,I~,“,,, .,.,a&‘6 the Lll” m.nee IBLY.,., .y_L’“L”~L’L II‘WLIIVU Knudsen effusion cells, evaporation of monosulphides of lanthanum. praseodymium, neodymium and gadolinium is investigated in the temoerature interval of 1800 to 2300°K. The values of heats of evaporation reactions, dissociation energies of gaseous monosulphihes and heats of formation of solid monosulphides are calculated. S P Gordienko and B V Fenochka, Thermouhys Prop of‘ Solids. Colt. Nauka Moscow
1973, 151-154
(in Russia). _
_ _
37 118. Investigation of structure and electrical conductivity of triple
system ZrO,-Ce02-Co0 at high temperatures. (USSR) The aim of described investigations was to prepare homogeneous ceramics with mixed electron-ion conductivity in dependence on oxygen partial pressure. Using an X-ray diffractometer with copper anticathode, structure of the triple system ZrO,-CeOz-Co0 was studied. Electrical conductivity was measured in a vacuum apparatus in the temperature interval of 600 to 1600°C in ambients with various ,.Y.l”P” nor+;91 n+-en‘.lll-eE “AJ~“LL ~U’LLU‘ ~‘“.T.nL”~’ G V Dontsov, Thermophys Prop of Solids, Coil, Nauka Moscow~ 1973. 92-96 (in Russian). 37 119. Some thermophysical properties of pyrographite. (USSR)
Integral hemispherical emissivity, electrical resistivity, the coefficient of thermal conductivity and structure of pyrolytic graphite are investigated at temperatures up to 2400°C in a vacuum chamber at pressure 6 ,*: 10m4 torr. V A Petrov et al, Thermophysical Properties of Solids, Coil, Nauka Moscow
1973, 74-79 (in Russizn).
37 120. Investigation of thermophysical properties of dielectrics at high
temperatures. (USSR) A vacuum apparatus for investigation of thermophysical properties of dielectric materials at high temperatures up to 2500°K is described. The working medium is vacuum of 10m5 torr or inert gas, electronbeam heating or theriiial KidktiGi; Gf 2 !C%J-iiiC%$Fi fihi32iit 2iZ iijd as a source of power oscillations. R P Yurkchak et al, Thermophysical Properties of Solids, Coil, Nauka Moscow
1973, 83-87 (in Russian).
37 121. The problem of long fatigue life of metals at low temperatures.
(USSR) The present state of theoretical and experimental results on features of fatigue failure of metals at low temperatures in vacuum is reviewed. The results of investigation of fatigue of copper and armco-iron at low temperatures in vacuum are compared with optical and electron microscope observations of their surfzce. B I Verkin et al, Space Investigations in Ukraine, Coil, No 1, Nauk Dumka
Kiev 1973, 14-22 (in Russian). 37
122. Casting magnesium-lithium alloys. (USSR)
Mechanical strength of casting magnesium alloy containing 15 to .,n, io ;/O01P,.,l~. nmnnn is investigated at ioiii, rooiii aiid high teiiipeiatuies. V P Latenko et al, Spare Investigations in Ukraine, Coil, No 1, Nauk Dumka Kiev 1973, 22-28 (in Russian). 37 123. The problem of long life of metals on periodic loading in vacuum
conditions. (USSR) The problem of action of vacuum conditions on strength of metals on periodic loading is considered. To investigate fatigue of metals in vacuum the installations with base pressure of 5 x 10m9 torr were built. Development of the fatigue process was investigated by observations in metallographical and electron microscopes. The results of investigations on the life of copper at periodic loading in dependence on oxygen pressure and total pressure are reported in the pressure interval of lo3 to 10v9 torr. The pressure dependence of life of armco-iron at periodic loading is also presented in the pressure range of 3 x 10z to lo-’ torr. The number of loading cycles before failure of copper increases linearly with pressure decrease down to 10Y9 torr (the limiting value of working pressure). Similar behaviour was observed for armco-iron. It is proposed that plastic deformation proceeds in vacuum more uniformly than in air. C__^_ lr*“rJIIyurr”rrJ r.____^r~--r~^__^ :__“IWLIII‘T, ,,I...^:._^ L”II, r-l, IYU 111-1 *r_..,. r) _L a,, _I 3yoce D r1 -,__1.1_ Vt!TK,”er rrr 1, l”UUrr Dumka Kiev 1973, 28-38 (in Russian).
23
process resulted in excessive oxidation. Atter several experiments, neither of these results was found to be instrumental in the formation I\f “L
PYFPQ&,P .,,..,I.,“.,-
.,,rfalrc= “..--..--
oxid,= .,‘.._...
Rather --...-A--)
the
hvrlrirlino ..JY”Y”‘~
w.artinn IWU”LI”II
itwlf 1.&.“11
proved to be mechanistic. The purpose of this paper is to describe experiments which will reveal that excessive oxidation is due to hydrogen reaction, suggesting a water transport mechanism recently reported by Beavis. E J Femandez and D M Holloway, J I’uc Sci Technol, 11 (3), 1974, 612-613. 37 112. Surface analysis by appearance potential spectroscopy. (Germany) The appearance-potential-spectroscopy (APS) is applied to the observation of 3 different secondary products, which are emitted of a target during electron bombardment (E = 50 . . . 1000 eV): photons, Auger-electrons and secondary-electrons. The surface-processes of the target and details of the apparatus are discussed. Some spectra are shown which yield many informations. Especially the determinations of energy thresholds, chemical shifts and band structures are possible. 31 (A\ Oh1 .“” OS4tin C:ovmnn\ \.,. --, ,,*- ,,,. , . ...__.,. AII,.) -I \ *,, 1974 _/I .) 1 _“, 1AL Khne LS.“B.,)Vnlr,,,,m_Torh 37 113. Analyses of materials with a new high current secondary ion mass spectrometer. (Germany) A secondary ion mass spectrometer has been developed and built for material- and concentration profile analysis. It consists of a Duoplasmatron Ion source with primary beam formation system, target changer, secondary ion energy selector and quadrupole mass filter. Mass resolution, dynamic range and transmission of the secondary ion analyser were investigated comparing thermal and sputter ion detection. Material analysis of several standards and samples and concentration profile measurements of implanted Cs into SIC are made by means of this apparatus. (Austria) F Pichlmayer, Vukuum-Tech, 23 (4), 1974, 98-103 (in German). 37
114. Complex investigation of thermophysical properties of refractory substances. (USSR) lll:+i. ,:... lL” - r&&,“L”L ,.nrr,.rm +r.,W.m,,t..,r:ml ,.F ..,&-..,,*,..... ““111,tt., ,,,e a,,,, rllrlll‘“&llrJ~,r~l :,.~r~nt:“n*:-.., ,‘lrr~r,~~r,“,,J “L ,r,,crcr”ly materials, apparatuses have been built for investigation of evaporation, composition and pressure of vapour, heats of evaporation reactions (sublimation, dissociation, disproportionation), enthalpy and thermal capacity, electrical resistivity, emissivity coefficients and thermal conductivity in a broad temperature interval and for determination of temperatures of melting. The apparatuses contain hightemperature high-vacuum chambers, high-temperature high-vacuum chambers with vacuum balances, mass-spectrometers modified for high-temperature investigations and calorimeters for temperature ranges of 400 to 1300” K and 1200 to 2500°K. Pressure less than 2 x 10e5 torr is achieved in the vacuum chamber for investigation of electrical conductivity of conducting refractory materials in the temperature interval of 2000 to 4000°K. In the chamber for investigation of evaporation of refractory materials in the temperature interval of 2000 to 2500°K the pressure 5 x 10m7 torr is maintained. A S Bolgar et al, Thermophys Prop of Solids, Coil, Nauka Moscow, 1077 I,,a,
115-!4! ._<
liM _._YY R,,rrinn\ \..* .-,.,.
37 115. On the character of evaporation of carbides of transition metals. (USSR) Evaporation of titanium, zironcium, hafnium and tantalum carbides is investigated in a vacuum of 1 x 10d5 torr using the Langmuir method. Evaporation of three chromium carbides is investigated using the Knudsen method. The experimental results are explained on the basis of nature of elements forming the carbides and the character of bond in these compounds. A S Bolgar, Thermophys Prop of Solids, Coil, Nauka Moscow 1973, 142-146 (in Russian). 37
Thermodynamic functions of nonstoichiometric Vanadium monocarbides at high temperatures. (USSR) Enthalpy of vanadium monocarbide with various composition in the region of homogeneity is measured in a high-vacuum high-temperature calorimeter in the temperature interval of 1300 to 2500°K. The samples of vanadium carbide were prepared by direct synthesis in a vacuum furnace at pressure 6 x 10v5 torr and temperature 1800°C. _fP^I.‘J” F,.ll IYUUI(O LT^..I._,yl”JC”W X.c^^__... *u 0 ‘P....^L^..:n, 111, “I 1Tr.““-,.-L..” r% I ul CLlalllll8X ,,rr rrr”yrryJ 1D”__ I “p “, ti”,‘“J, LLU,, 1973, 147-151 (in Russian). 116.
37 117. Evaporation of monosulphides of rare earth metals. (USSR) TTo;nn rnc.rtrr\mdrir mdhnrl with r\f t.,ntnl,.m III.LL ,.til;~ntinn ULlllrULl”., “1 IUL,I~,“,,, .,.,a&‘6 the Lll” m.nee IBLY.,., .y_L’“L”~L’L II‘WLIIVU Knudsen effusion cells, evaporation of monosulphides of lanthanum. praseodymium, neodymium and gadolinium is investigated in the temoerature interval of 1800 to 2300°K. The values of heats of evaporation reactions, dissociation energies of gaseous monosulphihes and heats of formation of solid monosulphides are calculated. S P Gordienko and B V Fenochka, Thermouhys Prop of‘ Solids. Colt. Nauka Moscow
1973, 151-154
(in Russia). _
_ _
37 118. Investigation of structure and electrical conductivity of triple
system ZrO,-Ce02-Co0 at high temperatures. (USSR) The aim of described investigations was to prepare homogeneous ceramics with mixed electron-ion conductivity in dependence on oxygen partial pressure. Using an X-ray diffractometer with copper anticathode, structure of the triple system ZrO,-CeOz-Co0 was studied. Electrical conductivity was measured in a vacuum apparatus in the temperature interval of 600 to 1600°C in ambients with various ,.Y.l”P” nor+;91 n+-en‘.lll-eE “AJ~“LL ~U’LLU‘ ~‘“.T.nL”~’ G V Dontsov, Thermophys Prop of Solids, Coil, Nauka Moscow~ 1973. 92-96 (in Russian). 37 119. Some thermophysical properties of pyrographite. (USSR)
Integral hemispherical emissivity, electrical resistivity, the coefficient of thermal conductivity and structure of pyrolytic graphite are investigated at temperatures up to 2400°C in a vacuum chamber at pressure 6 ,*: 10m4 torr. V A Petrov et al, Thermophysical Properties of Solids, Coil, Nauka Moscow
1973, 74-79 (in Russizn).
37 120. Investigation of thermophysical properties of dielectrics at high
temperatures. (USSR) A vacuum apparatus for investigation of thermophysical properties of dielectric materials at high temperatures up to 2500°K is described. The working medium is vacuum of 10m5 torr or inert gas, electronbeam heating or theriiial KidktiGi; Gf 2 !C%J-iiiC%$Fi fihi32iit 2iZ iijd as a source of power oscillations. R P Yurkchak et al, Thermophysical Properties of Solids, Coil, Nauka Moscow
1973, 83-87 (in Russian).
37 121. The problem of long fatigue life of metals at low temperatures.
(USSR) The present state of theoretical and experimental results on features of fatigue failure of metals at low temperatures in vacuum is reviewed. The results of investigation of fatigue of copper and armco-iron at low temperatures in vacuum are compared with optical and electron microscope observations of their surfzce. B I Verkin et al, Space Investigations in Ukraine, Coil, No 1, Nauk Dumka
Kiev 1973, 14-22 (in Russian). 37
122. Casting magnesium-lithium alloys. (USSR)
Mechanical strength of casting magnesium alloy containing 15 to .,n, io ;/O01P,.,l~. nmnnn is investigated at ioiii, rooiii aiid high teiiipeiatuies. V P Latenko et al, Spare Investigations in Ukraine, Coil, No 1, Nauk Dumka Kiev 1973, 22-28 (in Russian). 37 123. The problem of long life of metals on periodic loading in vacuum
conditions. (USSR) The problem of action of vacuum conditions on strength of metals on periodic loading is considered. To investigate fatigue of metals in vacuum the installations with base pressure of 5 x 10m9 torr were built. Development of the fatigue process was investigated by observations in metallographical and electron microscopes. The results of investigations on the life of copper at periodic loading in dependence on oxygen pressure and total pressure are reported in the pressure interval of lo3 to 10v9 torr. The pressure dependence of life of armco-iron at periodic loading is also presented in the pressure range of 3 x 10z to lo-’ torr. The number of loading cycles before failure of copper increases linearly with pressure decrease down to 10Y9 torr (the limiting value of working pressure). Similar behaviour was observed for armco-iron. It is proposed that plastic deformation proceeds in vacuum more uniformly than in air. C__^_ lr*“rJIIyurr”rrJ r.____^r~--r~^__^ :__“IWLIII‘T, ,,I...^:._^ L”II, r-l, IYU 111-1 *r_..,. r) _L a,, _I 3yoce D r1 -,__1.1_ Vt!TK,”er rrr 1, l”UUrr Dumka Kiev 1973, 28-38 (in Russian).