Oxidation behavior of a Mo (Si, Al)(2)-based composite at 300-1000 degrees C
Artikel i vetenskaplig tidskrift, 2010
The oxidation behavior of a Mo (Si,Al)(2)-based composite of Mo(Si,Al)(2), Al2O3 and Mo-5(Si,Al)(3) (Kanthal Super ER) in synthetic air was investigated. The samples were oxidized isothermally for up to 72 h at 300-1000 degrees C using a thermobalance. The microstructure was analyzed by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Auger Electron Spectroscopy (AES) depth profiling. Broad ion beam milling (BIB) was used to prepare cross-sections. Oxidation behavior depended strongly on the composition of the substrate which consisted of a Mo(Si,Al)(2) matrix and the minority phases Mo-5(Si,Al)(3) and Al2O3. At 300-500 degrees C the mass gains were small with parabolic kinetics, oxidation resulting in a mixture of oxides that reflects the substrate composition. At 600 and 700 degrees C the oxide scale is thin and protective and depleted in molybdenum, a mass loss occurring due to MoO3 vaporization. At 1000 degrees C a protective alpha-alumina scale forms.
FILMS
RESISTANCE
RANGE
ALLOYS
scanning
Oxidation
SILICIDES
Multiphase intermetallics
Spectroscopic methods
773 K
Molybdenum silicides
MOSI2
various
MOSI2-BASED COMPOSITE
Electron microscopy
AL
HIGH-TEMPERATURE OXIDATION
Författare
Linda Ingemarsson
Chalmers, Kemi- och bioteknik, Oorganisk miljökemi
Mats Halvarsson
Chalmers, Teknisk fysik, Mikroskopi och mikroanalys
Josefin Engkvist
Högskolan i Dalarna
Torbjörn Jonsson
Chalmers, Teknisk fysik, Mikroskopi och mikroanalys
Kristina M Hellström
Oorganisk miljökemi 1
Lars-Gunnar Johansson
Chalmers, Kemi- och bioteknik, Oorganisk miljökemi
Jan-Erik Svensson
Chalmers, Kemi- och bioteknik, Oorganisk miljökemi
Intermetallics
0966-9795 (ISSN)
Vol. 18 4 633-640Ämneskategorier
Materialteknik
DOI
10.1016/j.intermet.2009.10.019