Oxidation of Ceramic Materials Based on HfB<sub>2</sub>-SiC under the Influence of Supersonic CO<sub>2</sub> Jets and Additional Laser Heating
The features of oxidation of ultra-high-temperature ceramic material HfB<sub>2</sub>-30 vol.%SiC modified with 1 vol.% graphene as a result of supersonic flow of dissociated CO<sub>2</sub> (generated with the use of high-frequency induction plasmatron), as well as under the i...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-09-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/24/17/13634 |
| Summary: | The features of oxidation of ultra-high-temperature ceramic material HfB<sub>2</sub>-30 vol.%SiC modified with 1 vol.% graphene as a result of supersonic flow of dissociated CO<sub>2</sub> (generated with the use of high-frequency induction plasmatron), as well as under the influence of combined heating by high-speed CO<sub>2</sub> jets and ytterbium laser radiation, were studied for the first time. It was found that the addition of laser radiation leads to local heating of the central region from ~1750 to ~2000–2200 °C; the observed temperature difference between the central region and the periphery of ~300–550 °C did not lead to cracking and destruction of the sample. Oxidized surfaces and cross sections of HfB<sub>2</sub>-SiC-C<sub>G</sub> ceramics with and without laser heating were investigated using X-ray phase analysis, Raman spectroscopy and scanning electron microscopy with local elemental analysis. During oxidation by supersonic flow of dissociated CO<sub>2</sub>, a multilayer near-surface region similar to that formed under the influence of high-speed dissociated air flows was formed. An increase in surface temperature with the addition of laser heating from 1750–1790 to 2000–2200 °C (short term, within 2 min) led to a two to threefold increase in the thickness of the degraded near-surface area of ceramics from 165 to 380 microns. The experimental results indicate promising applications of ceramic materials based on HfB<sub>2</sub>-SiC as part of high-speed flying vehicles in planetary atmospheres predominantly composed of CO<sub>2</sub> (e.g., Venus and Mars). |
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| ISSN: | 1661-6596 1422-0067 |