Abstract
The parabolic oxidation of nickel by oxygen and by air at atmospheric pressure has been studied in the temperature range 600 to 1400 C, in particular by thermogravimetric and micrographic techniques. The mechanism of the reaction has been determined; it has been shown in particular that the break in the Arrhenius plot of the kinetics, occurring at about 950 C, is the result of a stimulation of the diffusion across the nickel prot-oxide film above this temperature; this is the result of the presence of excess nickel vacancies in the film. A systematic study has also been made of the influence of the oxygen pressure P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) on the parabolic oxidation of nickel between 800 and 1400 C. In the range 1000 to 1400 C, the activation energy of the process decreases monotonously from 57 to 34 kcal/mole as P{sub O{sub 2}} decreases from 760 to 1 torr. Furthermore, it has been shown that the parabolic oxidation constant is proportional to P{sub O{sub 2}}{sup 1/n} the value of n is not invariant however in the temperature range examined, but decreases from 6 to about 3 when the temperature increases
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Berry, L
[1]
- Commissariat a l'Energie Atomique, Saclay (France). Centre d'Etudes Nucleaires
Citation Formats
Berry, L.
Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees.
France: N. p.,
1967.
Web.
Berry, L.
Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees.
France.
Berry, L.
1967.
"Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees."
France.
@misc{etde_20523289,
title = {Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees}
author = {Berry, L}
abstractNote = {The parabolic oxidation of nickel by oxygen and by air at atmospheric pressure has been studied in the temperature range 600 to 1400 C, in particular by thermogravimetric and micrographic techniques. The mechanism of the reaction has been determined; it has been shown in particular that the break in the Arrhenius plot of the kinetics, occurring at about 950 C, is the result of a stimulation of the diffusion across the nickel prot-oxide film above this temperature; this is the result of the presence of excess nickel vacancies in the film. A systematic study has also been made of the influence of the oxygen pressure P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) on the parabolic oxidation of nickel between 800 and 1400 C. In the range 1000 to 1400 C, the activation energy of the process decreases monotonously from 57 to 34 kcal/mole as P{sub O{sub 2}} decreases from 760 to 1 torr. Furthermore, it has been shown that the parabolic oxidation constant is proportional to P{sub O{sub 2}}{sup 1/n} the value of n is not invariant however in the temperature range examined, but decreases from 6 to about 3 when the temperature increases from 900 to 1400 C. Finally, a study has been made of the oxidation of nickel in carbon dioxide at atmospheric pressure between 750 and 1400 C. The main reaction is Ni + CO{sub 2} {yields} NiO + CO, and corresponds, with a good approximation, to the reaction of the metal with the oxygen produced by the thermal dissociation of the CO{sub 2}. (author) [French] L'oxydation parabolique du nickel avec l'oxygene et l'air a la pression atmospherique a ete etudiee dans l'intervalle de temperatures 600-1400 C, surtout par voies thermogravimetrique et micrographique. Le mecanisme de la reaction a ete precise; en particulier, il a ete montre que la brisure de la courbe d'Arrhenius traduisant sa cinetique, qui se produit a 950 C environ, resulte d'une stimulation de la diffusion dans la pellicule de protoxyde de nickel au dessous de cette temperature, par suite de la presence de lacunes de nickel excedentaires dans celle-ci. D'autre part, l'influence de la pression d'oxygene P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) sur l'oxydation parabolique du nickel a ete etudiee systematiquement entre 800 et 1400 C. Dans l'intervalle 1000-1400 C, l'energie d'activation du processus diminue de facon monotone depuis 57 jusqu'a 34 kcal/ mole lorsque P{sub O{sub 2}} decroit de 760 a 1 torr. De plus, la proportionnalite de la constante parabolique d'oxydation avec P{sub O{sub 2}}{sup 1/n} a ete etablie; toutefois la valeur de n n'est pas invariable dans l'intervalle de temperatures explore, mais diminue de 6 a environ 3 quand celle-ci s'eleve de 900 a 1400 C. Enfin, l'oxydation du nickel dans l'anhydride carbonique sous la pression atmospherique a ete etudiee entre 750 et 1400 C. Elle s'effectue presque exclusivement suivant la reaction: Ni + CO{sub 2} {yields} NiO + CO, et equivaut, avec une bonne approximation, a la reaction de ce metal avec l'oxygene qui resulte de la dissociation thermique du CO{sub 2}. (auteur)}
place = {France}
year = {1967}
month = {Nov}
}
title = {Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees}
author = {Berry, L}
abstractNote = {The parabolic oxidation of nickel by oxygen and by air at atmospheric pressure has been studied in the temperature range 600 to 1400 C, in particular by thermogravimetric and micrographic techniques. The mechanism of the reaction has been determined; it has been shown in particular that the break in the Arrhenius plot of the kinetics, occurring at about 950 C, is the result of a stimulation of the diffusion across the nickel prot-oxide film above this temperature; this is the result of the presence of excess nickel vacancies in the film. A systematic study has also been made of the influence of the oxygen pressure P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) on the parabolic oxidation of nickel between 800 and 1400 C. In the range 1000 to 1400 C, the activation energy of the process decreases monotonously from 57 to 34 kcal/mole as P{sub O{sub 2}} decreases from 760 to 1 torr. Furthermore, it has been shown that the parabolic oxidation constant is proportional to P{sub O{sub 2}}{sup 1/n} the value of n is not invariant however in the temperature range examined, but decreases from 6 to about 3 when the temperature increases from 900 to 1400 C. Finally, a study has been made of the oxidation of nickel in carbon dioxide at atmospheric pressure between 750 and 1400 C. The main reaction is Ni + CO{sub 2} {yields} NiO + CO, and corresponds, with a good approximation, to the reaction of the metal with the oxygen produced by the thermal dissociation of the CO{sub 2}. (author) [French] L'oxydation parabolique du nickel avec l'oxygene et l'air a la pression atmospherique a ete etudiee dans l'intervalle de temperatures 600-1400 C, surtout par voies thermogravimetrique et micrographique. Le mecanisme de la reaction a ete precise; en particulier, il a ete montre que la brisure de la courbe d'Arrhenius traduisant sa cinetique, qui se produit a 950 C environ, resulte d'une stimulation de la diffusion dans la pellicule de protoxyde de nickel au dessous de cette temperature, par suite de la presence de lacunes de nickel excedentaires dans celle-ci. D'autre part, l'influence de la pression d'oxygene P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) sur l'oxydation parabolique du nickel a ete etudiee systematiquement entre 800 et 1400 C. Dans l'intervalle 1000-1400 C, l'energie d'activation du processus diminue de facon monotone depuis 57 jusqu'a 34 kcal/ mole lorsque P{sub O{sub 2}} decroit de 760 a 1 torr. De plus, la proportionnalite de la constante parabolique d'oxydation avec P{sub O{sub 2}}{sup 1/n} a ete etablie; toutefois la valeur de n n'est pas invariable dans l'intervalle de temperatures explore, mais diminue de 6 a environ 3 quand celle-ci s'eleve de 900 a 1400 C. Enfin, l'oxydation du nickel dans l'anhydride carbonique sous la pression atmospherique a ete etudiee entre 750 et 1400 C. Elle s'effectue presque exclusivement suivant la reaction: Ni + CO{sub 2} {yields} NiO + CO, et equivaut, avec une bonne approximation, a la reaction de ce metal avec l'oxygene qui resulte de la dissociation thermique du CO{sub 2}. (auteur)}
place = {France}
year = {1967}
month = {Nov}
}