Documents disponibles écrits par cet auteur

Comparison between field and laboratory steam oxidation testing on aluminide coatings on P92 / A. Agüero in Materials and corrosion, Vol. 62 N° 6 (Juin 2011) 

Public ISBD [article]  in Materials and corrosion > Vol. 62 N° 6 (Juin 2011) . - pp. 561–568 Titre : Comparison between field and laboratory steam oxidation testing on aluminide coatings on P92 Type de document : texte imprimé Auteurs : A. Agüero, Auteur ; V. Gonzlez, Auteur ; M. Gutierrez, Auteur Année de publication : 2011 Article en page(s) : pp. 561–568 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Aluminide  coatings  Field  testing  Ferritic  steels  Power  plants  Steam  oxidation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Steam oxidation has become an important issue for steam power plants as operating temperatures increase from the current 550 to 600–650 °C. For the last 10 years several groups have been carrying out steam oxidation testing of both uncoated substrates and coatings in the laboratory. On the other hand, field testing results are very scarce. In this paper, a comparison of laboratory steam oxidation testing with field test results carried out by Alstom at the Kraftwerk Westfalen power station located in Hamm, Germany will be presented. Both slurry deposited aluminide coatings and uncoated P92 steel have been included in the study. Under steam (atmospheric pressure) and isothermal conditions in the laboratory at 650 °C, spallation of oxides formed on ferritic steels occurs after significantly longer time when compared to exposure to real operating conditions. Oxide spallation results in serious damage in steam power plants by obstructing heat exchanger tubes, erosion of valves and turbine blades, etc. Moreover, the thickness of the oxide scales formed under field testing conditions is significantly higher after similar exposure. On the other hand, aluminide coated P92, which exhibit thickness through cracks, have shown to be stable in the laboratory for up to 60 000 h at 650 °C under steam, without evidence of crack propagation. However, field test results indicate that some degree of crack propagation occurs but without causing substrate attack up to 21 700 h of exposure. Moreover, the aluminium oxide observed in both laboratory and field tested specimens is different. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005874/abstract [article] Comparison between field and laboratory steam oxidation testing on aluminide coatings on P92 [texte imprimé] / A. Agüero, Auteur ; V. Gonzlez, Auteur ; M. Gutierrez, Auteur . - 2011 . - pp. 561–568. Génie Mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 62 N° 6 (Juin 2011) . - pp. 561–568 Mots-clés : Aluminide  coatings  Field  testing  Ferritic  steels  Power  plants  Steam  oxidation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Steam oxidation has become an important issue for steam power plants as operating temperatures increase from the current 550 to 600–650 °C. For the last 10 years several groups have been carrying out steam oxidation testing of both uncoated substrates and coatings in the laboratory. On the other hand, field testing results are very scarce. In this paper, a comparison of laboratory steam oxidation testing with field test results carried out by Alstom at the Kraftwerk Westfalen power station located in Hamm, Germany will be presented. Both slurry deposited aluminide coatings and uncoated P92 steel have been included in the study. Under steam (atmospheric pressure) and isothermal conditions in the laboratory at 650 °C, spallation of oxides formed on ferritic steels occurs after significantly longer time when compared to exposure to real operating conditions. Oxide spallation results in serious damage in steam power plants by obstructing heat exchanger tubes, erosion of valves and turbine blades, etc. Moreover, the thickness of the oxide scales formed under field testing conditions is significantly higher after similar exposure. On the other hand, aluminide coated P92, which exhibit thickness through cracks, have shown to be stable in the laboratory for up to 60 000 h at 650 °C under steam, without evidence of crack propagation. However, field test results indicate that some degree of crack propagation occurs but without causing substrate attack up to 21 700 h of exposure. Moreover, the aluminium oxide observed in both laboratory and field tested specimens is different. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005874/abstract