Atmospheric corrosion studies in a decommissioned nuclear power plant

Metallic corrosion progresses at a very low rate at room temperature in a perfectly dry atmosphere and for practical purposes may be ignored, but on humid surfaces is a very relevant phenomenon. The mechanism is electrochemical, with an electrolyte constituted by an extremely thin moisture film of j...

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Detalles Bibliográficos
Autores: Morcillo, Manuel, Otero, Eduardo, Chico, Belén, Fuente, Daniel de la
Tipo de recurso: otro
Fecha de publicación:2010
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/84757
Acceso en línea:http://hdl.handle.net/10261/84757
Access Level:acceso abierto
Palabra clave:Metallic corrosion
Mechanism electrochemical
Atmospheric corrosion
Descripción
Sumario:Metallic corrosion progresses at a very low rate at room temperature in a perfectly dry atmosphere and for practical purposes may be ignored, but on humid surfaces is a very relevant phenomenon. The mechanism is electrochemical, with an electrolyte constituted by an extremely thin moisture film of just a few monolayers or an aqueous film of hundreds of microns in thickness due, for instance, to rain or dew (Rozenfeld, 1972; Barton, 1976; Feliu and Morcillo, 1982; Kucera & Mattson, 1986; Costa et al., 2006). A considerable part of the damage that atmospheric corrosion causes to structures and equipment may be attributed to the condensation of humidity as a result of periodic cooling of the air. The formation of dew depends on the relative humidity (RH) of the air and the change in the metal surface temperature. The drier the atmosphere, the more the temperature must fall in order for humidity to condense; while at high RH a slight drop in temperature can lead to the saturation in humidity of the atmosphere. The fraction of time in which an atmosphere presents a high RH level has been shown to be a good indicator of its potential aggressivity.