High-Temperature Oxidation of a High Silicon SiMo Spheroidal Cast Iron in Air with <i>In Situ</i> Change in H<sub>2</sub>O Content - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Materials Science Forum Année : 2018

High-Temperature Oxidation of a High Silicon SiMo Spheroidal Cast Iron in Air with In Situ Change in H2O Content

Résumé

Exhaust manifolds for diesel engines are made of high-Si ferritic nodular cast irons. It is experimentally well established that their oxidation kinetics are highly sensitive to the presence of water vapor, though the mechanism for such an effect is still controversial. In the present work, isothermal oxidation tests were performed on a SiMo nodular cast iron at 700 °C and 800 °C in dry and humid air for 25 and 50 hours. Other samples were oxidized for 50 h with in-situ change in H2O content after 25 h, switching from dry air to humid air or the other way around. Samples were then analyzed using XRD, SEM-EDS and Raman spectroscopy. Thermogravimetric records clearly showed the effect of temperature and environment on oxidation and decarburization. The kinetics of these phenomena depend on silica formation at the metal-oxide interface. At both temperatures,water vapor was seen to promote internal oxidation of Si instead of its external oxidation. This leads to higher oxidation rate at 700°C and higher decarburization rate at 800°C.

Domaines

Matériaux
Fichier principal
Vignette du fichier
Ebel_21396.pdf (1.43 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-02059435 , version 1 (06-03-2019)

Identifiants

Citer

André Ebel, Serge Yapi Brou, Benoît Malard, Jacques Lacaze, Daniel Monceau, et al.. High-Temperature Oxidation of a High Silicon SiMo Spheroidal Cast Iron in Air with In Situ Change in H2O Content. Materials Science Forum, 2018, Science and Processing of Cast Iron XI, 925, pp.353-360. ⟨10.4028/www.scientific.net/MSF.925.353⟩. ⟨hal-02059435⟩
88 Consultations
342 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More