Microstructural, strength, and creep characterization of Sylramic™, Sylramic™-iBN and super Sylramic™-iBN SiC fibers
| Autor: | Ramakrishna T. Bhatt, D.F. Johnson, R.B Rogers, Francisco Solá, L.J. Evans |
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| Rok vydání: | 2021 |
| Předmět: |
010302 applied physics
Argon Materials science chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology Microstructure 01 natural sciences Grain size Amorphous carbon Creep chemistry visual_art 0103 physical sciences Materials Chemistry Ceramics and Composites visual_art.visual_art_medium Thermal stability Ceramic Composite material 0210 nano-technology Chemical composition |
| Zdroj: | Journal of the European Ceramic Society. 41:4697-4709 |
| ISSN: | 0955-2219 |
| DOI: | 10.1016/j.jeurceramsoc.2021.03.024 |
| Popis: | The chemical composition, microstructure, strength, and thermal stability of polymer-derived Sylramic™ SiC fibers fabricated by Dow Corning and COI Ceramics, Inc., and nitrogen-treated Sylramic™ SiC fibers, referred to as Sylramic™-iBN and Super Sylramic™-iBN SiC fibers, were investigated and compared. The baseline Sylramic™ SiC fibers fabricated by both vendors as well as the nitrogen-treated Sylramic™ SiC fibers are composed mostly of β-SiC (∼97 wt%) with small amounts of TiB2 (∼2 wt%), amorphous carbon (∼1 wt%) and trace amounts of B4C. Most of the amorphous carbon is segregated at the core/interior of the fibers. Both baseline and nitrogen-treated Sylramic™ SiC fibers have similar grain size and pore size distribution, except for a thin layer of in-situ grown crystalline BN (30–70 nm) on the surface of Sylramic™-iBN and Super Sylramic™-iBN fibers. Wide variation in strength within a batch as well as between batches is observed in both baseline and nitrogen-treated Sylramic™ SiC fibers but both types of fibers are microstructurally stable at temperatures to 1800 °C in argon and nitrogen environments compared to Nicalon™-S and Tyranno®-SA SiC fibers. Under the same creep condition, Super Sylramic™-iBN fibers show better creep resistance compared to Sylramic™, Sylramic™-iBN, Hi-Nicalon™-S, and Tyranno®-SA fibers. Possible reasons for strength variability and the mechanism of in-situ BN formation on Sylramic™ SiC fibers are discussed. |
| Databáze: | OpenAIRE |
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