EDP Sciences Journals List
Issue J. Phys. IV France
Volume 03, Number C9, Décembre 1993
Proceedings of the 3rd International Symposium on High Temperature Corrosion and Protection of Materials
Actes du 3ème Colloque International sur la Corrosion et la Protection des Matériaux à Haute Température
Page(s) C9-439 - C9-445
DOI http://dx.doi.org/10.1051/jp4:1993946

Proceedings of the 3rd International Symposium on High Temperature Corrosion and Protection of Materials
Actes du 3ème Colloque International sur la Corrosion et la Protection des Matériaux à Haute Température

J. Phys. IV France 03 (1993) C9-439-C9-445

DOI: 10.1051/jp4:1993946

Oxydation du zircaloy-4 dans l'air à haute température

Sulistijono1, A. Bouden1, M. Cherfaoui2, G. Beranger1 and M. Lambertin1

1  LG2mS (URA 1505 CNRS), Université de Technologie de Compiègne, B.P. 649, F-60206 Compiègne Cedex, France
2  CETIM, Service "Essais et Mesures Physiques", 52 Avenue Félix Louat, F-60304 Senlis, France


Abstract
The oxidation of zircaloy-4 in air was studied in the temperature range 350-750 °C. The oxidation kinetics cannot be described by a single rate law. At the beginning of the reaction, the rate decreases regularly. Then, after a few hours, an acceleration is observed and finally a linear law is obeyed. The morphological observations show that the acceleration is related to the formation of cracks in the oxide scale. Moreover, two different zirconia phases (monoclinic and tetragonal) are identified. When the kinetic transition occurs, the tetragonal phase partially disappears. All these observations show that a mechanism, similar to that proposed to describe the oxidation of zircaloy-4 in steam, may be used to describe the reaction. In parallel, the oxidation reaction was studied by using acoustic emission. The frequency, the amplitude and the energy were used to characterize the signal. Typical groups were identified and their appearance was strongly correlated to the different parts of the reaction.



© EDP Sciences 1993