Quantitative µ-CT Analysis of Scale Topology Formed during Oxidation of High SiMo Cast Iron
Abstract
High SiMo cast iron components in automotive exhaust systems are exposed to high-temperature oxidation over time. Quantitative analysis of formed oxide scale is therefore important for the assessment of a component durability. The brittle nature of multilayered scale and thermal stress limits capture of a true topology using traditional 2D destructive cut and polish methods. In this study, nondestructive high spatial-resolution 3D µCT analysis was performed on 2.90-mm-diameter oxidized specimens which permitted direct observation with 3.5 µm pixel resolution. The specimens were oxidized in three sequential time steps for a total 100 h at 700 °C and 800 °C in air and combustion gas atmospheres. A MATLAB-coded algorithm was used to quantify the topology, thickness variation in internal and external scale layers, and scale/metal interface unevenness. Scale topology was linked to oxidation temperature and gas atmosphere. A water vapor environment increases scale/metal interface unevenness and scale layer thickness irregularity which were related to an accelerated oxidation rate.
Recommended Citation
S. N. Lekakh et al., "Quantitative µ-CT Analysis of Scale Topology Formed during Oxidation of High SiMo Cast Iron," Oxidation of Metals, vol. 94, no. 3 thru 4, pp. 251 - 264, Springer, Oct 2020.
The definitive version is available at https://doi.org/10.1007/s11085-020-09989-0
Department(s)
Materials Science and Engineering
Keywords and Phrases
Micro-CT; Morphology; Scale; SiMo Cast Iron
International Standard Serial Number (ISSN)
0030-770X; 1573-4889
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2020 Springer, All rights reserved.
Publication Date
01 Oct 2020
