| Oxidation resistance of Ti-Al-C MAX phases-based bulk materials and coatings at high-temperatures Tetiana Prikhna1; Orest Ostash2; Alexander Kuprin3; Viktoriya Podhurska4; Thierry Cabioc'h5; Tetiana Serbenyuk6; Viktor Moshchil7; Vladimir Sverdun6; Myroslav Karpets7; Semyon Ponomarov8; Alexandra Starostina6; Fernand D. S. Marquis9; Florian Kongoli10; 1V. BAKUL INSTITUTE NASU, Kiev, Ukraine; 2KARPENKO PHYSICAL-MECHANICAL INSTITUTE OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Lviv, Ukraine; 3NATIONAL SCIENCE CENTER KHARKOV INSTITUTE OF PHYSICS AND TECHNOLOGY, Kharkov, Ukraine; 4PHYSICO-MECHANICAL INSTITUTE OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Lviv, Ukraine; 5UNIVERSITE DE POITIERS, CNRS/LABORATOIRE PHYMAT, Chasseneuil Futuroscope Cedex, France; 6INSTITUTE FOR SUPERHARD MATERIALS OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Kiev, Ukraine; 7INSTITUTE FOR SUPERHARD MATERIALS, Kiev, Ukraine; 8INSTITUTE OF SEMICONDUCTOR PHYSICS, Kiev, Ukraine; 9UNITED NANO TECHNOLOGIES (UNT) AND INTEGRATED MATERIALS TECHNOLOGIES AND SYSTEMS (IMTS), Rapid City, United States; 10FLOGEN TECHNOLOGIES, Mont-Royal, Canada; PAPER: 284/AdvancedMaterials/Regular (Oral) SCHEDULED: 16:20/Mon. 28 Nov. 2022/Saitong ABSTRACT: The, results of variations of structure in oxidizing atmosphere at high temperatures (after heating and thermocycling up to 600 – 1400 <sup>o</sup>C), and electrical conductivity (after long time heating at 600 <sup>o</sup>C) of MAX Ti<sub>2</sub>AlC-, Ti<sub>3</sub>AlC<sub>2</sub>- and (Ti,Nb)<sub>3</sub>AlC<sub>2</sub>-based bulk materials with different porosity (prepared by synthesis in vacuum and/or by hot pressing) and coatings (vacuum-arc deposited) are presented. The characteristics of highly dense Ti-Al-C composite bulks and vacuum-arc deposited 6 m thick coatings before and after heating at 600 <sup>°</sup>C in air for 1000 h were compared. High electrical conductivity ((The, results of variations of structure in oxidizing atmosphere at high temperatures (after heating and thermocycling up to 600 – 1400 <sup>o</sup>C), and electrical conductivity (after long time heating at 600 <sup>o</sup>C) of MAX Ti<sub>2</sub>AlC-, Ti<sub>3</sub>AlC<sub>2</sub>- and (Ti,Nb)<sub>3</sub>AlC<sub>2</sub>-based bulk materials with different porosity (prepared by synthesis in vacuum and/or by hot pressing) and coatings (vacuum-arc deposited) are presented. The characteristics of highly dense Ti-Al-C composite bulks and vacuum-arc deposited 6 µm thick coatings before and after heating at 600 °C in air for 1000 h were compared. High electrical conductivity (<i>delta</i> m/S =1.3•10<sup>6</sup> S/m) of the highly resistant toward oxidation (<i>delta</i> m/S=0.07 mg/cm<sup>2</sup>) Ti-Al-C coating was preserved after long-term heating in air. It was found that the specimen surface layers of MAX-phases Ti<sub>3</sub>AlC<sub>2</sub> and Ti<sub>2</sub>AlC based bulks and chromium-containing Crofer 22APU steel became semiconductors because of high-temperature long-term oxidation (at 600 <sup>°</sup>C). The vacuum-arc deposited Ti-Al-C coating revealed high oxidation resistance and electrical conductivity along with good mechanical characteristics, namely nanohardness H (10 mN)= 9.5±1.5 GPa, and Young’s modulus E=190±10 GPa, which make it very promising for interconnects of solid oxide fuel cells (SOFCs). Acknowledgements The investigations were performed in the frames of the project NATO SPS G5773 “Advanced Material Engineering to Address Emerging Security Challenges” for 2020-2023, the project 03-03-20 of Ukrainian-Belorussian cooperation for 2020-2021, and the projects III-3-20 (0779), III-5-19 (0778), and II-5-19 (ІНМ-29/20) supported by the National Academy of Sciences of Ukraine. |
