20.500.12556/RUL-169759 Element redistribution in the oxide scale during air oxidation of Kanthal AF alloy The oxidation mechanism of Kanthal AF (FeCrAl alloy) was studied in the temperature range of 800–1200 °C through isothermal and thermo-cyclic oxidation tests. At 800 °C, tests involved 12-hour cycles (up to 36 cycles), while at 1000 °C and 1200 °C, they were conducted isothermally (up to 432 hours). Oxidation constants, oxide scale thickness, surface microstructure, and elemental composition were analyzed using TGA, SEM-EDXS, TEM, AES, XPS, GIXRD, and ToF-SIMS. The results show that the Al$_2$O$_3$ layer has a multilayer structure, defined by a naturally formed thin Cr-rich oxide layer on the alloy surface, which exhibits temperature-dependent selective permeability of metal cations, influencing the oxide scale growth. At 800 °C, inward oxide diffusion dominates due to limited cation permeability in the Cr-rich layer, while at higher temperatures, outward growth of the alumina scale is facilitated by increased permeability to metal cations. Despite the low Mg concentration in the alloy (0.01 wt.%), Mg diffuses into the alumina rapidly, forming Mg-Al-Fe oxides that transform into MgAl$_2$O$_4$ spinel, impacting scale integrity and adhesion due to associated porosity. Consequently, Mg is considered an undesirable impurity, even at trace levels. Titanium forms separate oxides in the alumina scale, while zirconium and yttrium incorporate uniformly into the alumina scale. Kanthal alloys oxidation tests protective alumina scale high temperature oxidation FeCrAl alloys element distribution in alumina scale zlitine FeCrAl zlitine jeklo oksidacija true false true Angleški jezik Slovenski jezik Članek v reviji 2025-06-09 09:13:28 2025-06-09 09:13:37 2025-06-11 04:28:58 0000-00-00 00:00:00 2024 0 0 Str. 8720-8729 Vol. 33 Nov./Dec. 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.1/.2 2214-0697 10.1016/j.jmrt.2024.11.169 216298243 1-s2.0-S2238785424026978-main.pdf 1-s2.0-S2238785424026978-main.pdf 1 552E387897EBCE7391EC1D12005F1337 438db5e97576204e8348b9c313bb55f070cd3dac07741ba1824b3ffa9bb16c6a 76bb241f-4500-11f0-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=211423 https://www.sciencedirect.com/science/article/pii/S2238785424026978 0 c6985632-44ff-11f0-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=211420 Naravoslovnotehniška fakulteta Fakulteta za kemijo in kemijsko tehnologijo 0 0 0