Oxidation behavior of a Mo (Si, Al)(2)-based composite at 300-1000 degrees C
Journal article, 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.

Oxidation

FILMS

773 K

Molybdenum silicides

MOSI2-BASED COMPOSITE

Multiphase intermetallics

Spectroscopic methods

RESISTANCE

HIGH-TEMPERATURE OXIDATION

AL

MOSI2

various

scanning

SILICIDES

ALLOYS

Electron microscopy

RANGE

Author

Linda Ingemarsson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Mats Halvarsson

Chalmers, Applied Physics, Microscopy and Microanalysis

Josefin Engkvist

Hogskolan Dalarna

Torbjörn Jonsson

Chalmers, Applied Physics, Microscopy and Microanalysis

Kristina M Hellström

Chalmers

Lars-Gunnar Johansson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Jan-Erik Svensson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Intermetallics

0966-9795 (ISSN)

Vol. 18 4 633-640

Subject Categories

Materials Engineering

DOI

10.1016/j.intermet.2009.10.019

More information

Latest update

11/5/2018