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Improved oxidation behavior of Hf0.11Al0.20B0.69 in comparison to Hf0.28B0.72 magnetron sputtered thin films.
- Source :
- Scientific Reports; 9/17/2024, Vol. 14 Issue 1, p1-13, 13p
- Publication Year :
- 2024
-
Abstract
- The oxidation resistance of Hf<subscript>0.28</subscript>B<subscript>0.72</subscript> and Hf<subscript>0.11</subscript>Al<subscript>0.20</subscript>B<subscript>0.69</subscript> thin films was investigated comparatively at 700 °C for up to 8 h. Single-phase solid solution thin films were co-sputtered from HfB<subscript>2</subscript> and AlB<subscript>2</subscript> compound targets. After oxidation at 700 °C for 8 h an oxide scale thickness of 31 ± 2 nm was formed on Hf<subscript>0.11</subscript>Al<subscript>0.20</subscript>B<subscript>0.69</subscript> which corresponds to 14% of the scale thickness measured on Hf<subscript>0.28</subscript>B<subscript>0.72</subscript>. The improved oxidation resistance can be rationalized based on the chemical composition and the morphology of the formed oxide scales. On Hf<subscript>0.28</subscript>B<subscript>0.72</subscript> the formation of a porous, O, Hf, and B-containing scale and the formation of crystalline HfO<subscript>2</subscript> is observed. Whereas on Hf<subscript>0.11</subscript>Al<subscript>0.20</subscript>B<subscript>0.69</subscript> a dense, primarily amorphous scale containing O, Al, B as well as approximately 3 at% of Hf forms, which reduces the oxidation kinetics significantly by passivation. Benchmarking Hf<subscript>0.11</subscript>Al<subscript>0.20</subscript>B<subscript>0.69</subscript> with Ti–Al-based boride and nitride thin films with similar Al concentrations reveals superior oxidation behavior of the Hf-Al-based thin film. The incorporation of few at% of Hf in the oxide scale decelerates oxidation kinetics at 700 °C and leads to a reduction in oxide scale thickness of 21% and 47% compared to Ti<subscript>0.12</subscript>Al<subscript>0.21</subscript>B<subscript>0.67</subscript> and Ti<subscript>0.27</subscript>Al<subscript>0.21</subscript>N<subscript>0.52</subscript>, respectively. Contrary to Ti–Al-based diborides, Hf<subscript>0.11</subscript>Al<subscript>0.20</subscript>B<subscript>0.69</subscript> shows excellent oxidation behavior despite B-richness. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 20452322
- Volume :
- 14
- Issue :
- 1
- Database :
- Complementary Index
- Journal :
- Scientific Reports
- Publication Type :
- Academic Journal
- Accession number :
- 179761153
- Full Text :
- https://doi.org/10.1038/s41598-024-72134-3