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The kinetics of oxide film growth on Maraging steel as described by space‐charge effects
Author(s) -
Greyling C. J.,
Kotzé I. A.,
Viljoen P. E.
Publication year - 1990
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/sia.740160161
Subject(s) - auger electron spectroscopy , oxide , kinetics , spinel , maraging steel , sputtering , analytical chemistry (journal) , materials science , argon , thin film , metallurgy , chemistry , nanotechnology , physics , organic chemistry , chromatography , quantum mechanics , nuclear physics
The oxidation kinetics of a grade 300 maraging steel in air at temperatures ranging from 300 to 600 °C have been determined using Auger electron spectroscopy in conjunction with argon ion sputtering. A limited‐thickness type of growth was observed up to the relatively high temperature of 480 °C. Above 480 °C, the kinetics were parabolic. A thin gold layer sputtered onto the surface before oxidation resulted to a change in the kinetics from limited‐thickness to approximately parabolic growth at temperatures below 480 °C, while it remained parabolic above 480°C. The limited‐thickness oxide growth is described in terms of space‐charge effects, as outlined by the theory of Formhold. The insulating properties of a thin mixed spinel oxide present at the metaloxide interface is critical in bringing about the space charge in the oxide. A change in the electrical conductivity of the mixed spinel is associated with a change in the oxidation kinetics.