| Autor: |
Rafael Guimarães de Sá, Daniel Doni Jayaseelan, Peter Brown, William E. Lee |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
Journal of the European Ceramic Society. 31:361-368 |
| ISSN: |
0955-2219 |
| DOI: |
10.1016/j.jeurceramsoc.2010.10.013 |
| Popis: |
A novel reactive infiltration processing (RIP) technique was employed to infiltrate porous carbon fibre reinforced carbon (C/C) composite hollow tubes with ultra high temperature ceramic (UHTC) particles such as ZrB 2 . The C/C composite tubes had initial porosity of ∼60% with a bimodal (10 μm and 100 μm) pore size distribution. A slurry with 40–50% ZrB 2 solid loading particles was used to infiltrate the C/C tubes. Our approach combines in situ ZrB 2 formation with coating of fine ZrB 2 particles on carbon fibre surfaces by a reactive processing method. A Zr and B containing diphasic gel was first prepared using inorganic–organic hybrid precursors of zirconium oxychloride (ZrOCl 2 ·8H 2 O), boric acid, and phenolic resin as sources of zirconia, boron oxide, and carbon, respectively. Then commercially available ZrB 2 powder was added to this diphasic gel and milled for 6 h. The resultant hybrid slurry was vacuum infiltrated into the porous hollow C/C tubes. The infiltrated tubes were dried and fired for 3 h at 1400 °C in flowing Ar atmosphere to form and coat ZrB 2 on the carbon fibres in situ by carbothermal reaction. Microstructural observation of infiltrated porous C/C composites revealed carbon fibres coating with fine nanosized (∼100 nm) ZrB 2 particles infiltrated to a depth exceeding 2 mm. Ultra high temperature ablation testing for 60 s at 2190 °C suggested formation of ZrO 2 around the inner bore of the downstream surface. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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