Phase, composition and structure changes of CoCrNi-based concentrated alloys resulting from high temperature oxidation

0531256 - ÚFP 2021 RIV CH eng J - Journal Article
Vilémová, Monika - Hadraba, Hynek - Weiss, Zdeněk - Lukáč, František - Csáki, Štefan - Chlup, Zdeněk - Matějíček, Jiří - Chráska, Tomáš
Phase, composition and structure changes of CoCrNi-based concentrated alloys resulting from high temperature oxidation.
Materials. Roč. 13, č. 10 (2020), č. článku 2276. E-ISSN 1996-1944
R&D Projects: GA ČR(CZ) GA17-23964S; GA MŠMT(CZ) EF16_019/0000760
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:61389021 ; RVO:68378271 ; RVO:68081723
Keywords : Cr C dissolution 23 6 * CrMnFeCoNi * FeCoNiCr * High-entropy alloys * Medium-entropy alloys * Oxide dispersion strengthening * Passivation * Spark plasma sintering * Y-Ti complex oxide nanoparticles * Y O particles 2 3
OECD category: Materials engineering; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D); Materials engineering (UFM-A)
Impact factor: 3.623, year: 2020
Method of publishing: Open access
https://www.mdpi.com/1996-1944/13/10/2276

In this work, CoCrNi, FeCoCrNi and CoCrFeMnNi concentrated alloys with a Y-Ti oxide particle dispersion were prepared by mechanical alloying and Spark Plasma Sintering. The alloy consists of an FCC Ni-based matrix with a Y-Ti oxide dispersion and additional phases of Cr23C6 and Cr2O3. The effect of Fe, Mn, and Y-Ti oxide particles on the formation of oxide scales and the composition of the adjacent CoCrNi and FeCoCrNi alloys was studied. It was found that alloys without Mn in their composition form a protective Cr2O3 scale. The Cr23C6 particles provide an alternative mechanism for balancing the chromium loss during the oxidation. Y and Ti from the oxide particles participate in the formation of the protective oxide scales. Fe promotes Y and especially Ti diffusion through the Cr2O3 scale, resulting in the formation of Ti-depleted regions in the alloy. The findings will serve for the further development of these new materials.
Permanent Link: http://hdl.handle.net/11104/0310183