Date of Award
Master of Science
Dr. N.S. McIntyre
A comprehensive assessment of the oxide grown on Incoloy alloy 800 has enhanced the understanding of the oxide film’s composition and growth, specifically for application as a protective pre-treatment. Surface morphology, chemical composition, oxide film thicknesses and kinetics have all been studied using, principally, X-ray Photoelectron Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS). Gas-phase oxidations were performed at temperatures of 300°C in atmospheres of 1% O2 at 1 atm for up to 24h. All samples displayed similar oxidation behaviour over the exposure period. A multi-layered oxide film was detected and was composed primarily
of an exterior y-Fe20_3 with a small Cr2 0 3 layer at the oxide-metal interface. Small additions of NiCr2C>4 and NiFe2C>4 were distributed throughout the film. Direct logarithmic kinetics were observed and were indicative of an oxide film that was self- limiting in its growth at the experimental temperatures. The influence of grain size and minor cold work, in the form of localized indentation, on the oxide film formed on Incoloy 800 has been studied.
Edwards, Michael W., "THE STUDY OF GAS-PHASE OXIDATION IN INCOLOY 800 BY SURFACE ANALYTICAL TECHNIQUES" (2011). Digitized Theses. 3596.