Corrosion of ceramic silicon carbide in hydrofluoric acid

0544788 - ÚFP 2022 RIV CZ eng J - Journal Article
Brožek, Vlastimil - Živný, Oldřich - Mastný, L. - Matušek, M. - Pokorný, P.
Corrosion of ceramic silicon carbide in hydrofluoric acid.
Ceramics - Silikáty. Roč. 65, č. 2 (2021), s. 158-169. ISSN 0862-5468. E-ISSN 1804-5847
R&D Projects: GA ČR(CZ) GC17-10246J
Institutional support: RVO:61389021
Keywords : Corrosion resistance * Hydrofluoric acid * Silicon carbide
OECD category: Materials engineering
Impact factor: 1.010, year: 2021
Method of publishing: Open access
https://www.irsm.cas.cz/materialy/cs_content/2021_doi/Brozek_CS_2021_0015.pdf

Silicon carbide usable in mechanical or electrical engineering is produced in various purity grades and exhibits a large number of crystal structure variants. As for use in the chemical field, it is commonly stated that it is highly resistant in acid media but not suitable for use in alkaline media. This paper discusses the resistance of compact silicon carbide to hydrofluoric acid. The compact silicon carbide has been prepared by sintering using the SSiC method with or without binders based on scandium oxide Sc2O3 and calcium fluoride CaF2. The purest silicon carbide sample of cubic 3C structure sintered without a binder was almost insoluble in hydrofluoric acid. It has been shown, however, that pure silicon carbide is perfectly insoluble in hydrofluoric acid irrespective of the structure variants detected in the samples (3C, 4H, 6H, 15R). The corrosion stability of the compact ceramics is affected by the residual SiO2 content (together with other impurities) in imperfect SiC preparations, and it is influenced by the choice and chemical properties of the chosen ceramic binder as well.
Permanent Link: http://hdl.handle.net/11104/0321595