Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Nov 29;15(23):8507.
doi: 10.3390/ma15238507.

Investigation of the Effect of Supersonic Flow of Dissociated Nitrogen on ZrB2-HfB2-SiC Ceramics Doped with 10 vol.% Carbon Nanotubes

Elizaveta P Simonenko  1 , Nikolay P Simonenko  1 , Anatoly F Kolesnikov  2 , Aleksey V Chaplygin  2 , Anton S Lysenkov  3 , Ilya A Nagornov  1 , Artem S Mokrushin  1 , Nikolay T Kuznetsov  1
Affiliations

Investigation of the Effect of Supersonic Flow of Dissociated Nitrogen on ZrB2-HfB2-SiC Ceramics Doped with 10 vol.% Carbon Nanotubes

Elizaveta P Simonenko et al. Materials (Basel). .

Abstract

The method of fabricating dense ultra-high temperature ceramic materials ZrB2−HfB2−SiC−CCNT was developed using a combination of sol-gel synthesis and reaction hot pressing approaches at 1800 °C. It was found that the introduction of multilayer nanotubes (10 vol.%) led to an increase in the consolidation efficiency of ceramics (at temperatures > 1600 °C). The obtained ZrB2−HfB2−SiC and ZrB2−HfB2−SiC−CCNT materials were characterized by a complex of physical and chemical analysis methods. A study of the effects on the modified sample ZrB2−HfB2−SiC−CCNT composition speed flow of partially dissociated nitrogen, using a high-frequency plasmatron, showed that, despite the relatively low temperature established on the surface (≤1585 °C), there was a significant change in the chemical composition and surface microstructure: in the near-surface layer, zirconium−hafnium carbonitride, amorphous boron nitride, and carbon were present. The latter caused changes in crucial characteristics such as the emission coefficient and surface catalyticity.

Keywords: CNT; SiC; UHTC; borides; carbon nanotubes; induction plasmatron.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Figure 1
Figure 1
Shrinkage curves as a function of temperature and hot-pressing pressure for ZHS (left) and ZHSC (right) samples.
Figure 2
Figure 2
X-ray diffraction patterns of ZHS (1), ZHSC (2), and the surface of the ZHSC sample after exposure to a supersonic flow of dissociated nitrogen (3); the inset area in the range 2θ = 41.5–42.5°, in which the position of the maximum intensity reflexes of ZrB2 [66] and HfB2 [67].
Figure 3
Figure 3
Raman spectra of the surface of ceramic samples ZHS (1), ZHSC (2), as well as the surface of the ZHSC sample after exposure to a supersonic flow of dissociated nitrogen (3).
Figure 4
Figure 4
Microstructure of ZHS and ZHSC samples based on SEM data (based on secondary electron detector data), accelerating voltage 2 kV.
Figure 5
Figure 5
Mapping the distribution of elements Si, Zr, and Hf on thin sections of samples ZHS and ZHSC (EDX).
Figure 6
Figure 6
Variation of the color temperature in the center of the sample face (T), plasmatron generator power by anode supply (N) and pressure in the pressure chamber (P) in the experiment on heat exchange of ZHSC ceramics in an underexpanded high-enthalpy nitrogen jet.
Figure 7
Figure 7
The thermal images at specific moments of the experiment and typical temperature distribution over the diameter of the ZHSC sample (300 s).
Figure 8
Figure 8
Microstructure of ZHSC sample surface after thermochemical treatment; SEM, accelerating voltage 1 kV: (a–c)—according to secondary electron detector data, (d)—in contrast mode by mean atomic number.
Figure 9
Figure 9
(a) ZHSC surface microstructure after thermochemical treatment; (b) SEM, accelerating voltage 20 kV.
Figure 10
Figure 10
The elemental distribution mapping ((a,b), zirconium–blue pixels, hafnium–green): X-ray elemental microanalysis data of the entire microphotograph area (a) and individual sections (b), as well as the corresponding EDX spectrum (c), enlarged fragment EDX spectrum (d).
Figure 11
Figure 11
The temperature dependences of ΔGr(T), calculated for reactions (1–10) in the temperature range 1200–2300 K using the IVTANTERMO software package with a built-in thermodynamic database; numbers denote reaction numbers.
See this image and copyright information in PMC

References

    1. Simonenko E.P., Sevast’yanov D.V., Simonenko N.P., Sevast’yanov V.G., Kuznetsov N.T. Promising Ultra-High-Temperature Ceramic Materials for Aerospace Applications. Russ. J. Inorg. Chem. 2013;58:1669–1693. doi: 10.1134/S0036023613140039. - DOI
    1. Justin J.-F., Julian-Jankowiak A., Guérineau V., Mathivet V., Debarre A. Ultra-High Temperature Ceramics Developments for Hypersonic Applications. CEAS Aeronaut. J. 2020;11:651–664. doi: 10.1007/s13272-020-00445-y. - DOI
    1. Pellegrini C., Balat-Pichelin M., Rapaud O., Bêche E. Oxidation Resistance of Zr- and Hf-Diboride Composites Containing SiC in Air Plasma up to 2600 K for Aerospace Applications. Ceram. Int. 2022;48:2177–2190. doi: 10.1016/j.ceramint.2021.09.310. - DOI
    1. Nisar A., Hassan R., Agarwal A., Balani K. Ultra-High Temperature Ceramics: Aspiration to Overcome Challenges in Thermal Protection Systems. Ceram. Int. 2022;48:8852–8881. doi: 10.1016/j.ceramint.2021.12.199. - DOI
    1. Guérineau V., Vilmart G., Dorval N., Julian-Jankowiak A. Comparison of ZrB2-SiC, HfB2-SiC and HfB2-SiC-Y2O3 Oxidation Mechanisms in Air Using LIF of BO2(G) Corros. Sci. 2020;163:108278. doi: 10.1016/j.corsci.2019.108278. - DOI

LinkOut - more resources