This is an Accepted Manuscript version of the following article, accepted for publication in Materials at High Temperatures. Rebecca Higginson & Gordon Tatlock (2023) Microscopy of oxidation 11, Materials at High Temperatures, 40:4, 259, DOI: 10.1080/09603409.2023.2220229. It is deposited under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited.