| Autor: |
Chun-Liang Yeh, Je-An Peng |
| Jazyk: |
angličtina |
| Rok vydání: |
2016 |
| Předmět: |
|
| Zdroj: |
Metals, Vol 6, Iss 10, p 235 (2016) |
| Druh dokumentu: |
article |
| ISSN: |
2075-4701 |
| DOI: |
10.3390/met6100235 |
| Popis: |
Formation of MoSi2–Al2O3 composites with a broad range of the MoSi2/Al2O3 ratio was conducted by thermite-based combustion synthesis in the SHS mode. The addition of two thermite mixtures composed of MoO3 + 2Al and 0.6MoO3 + 0.6SiO2 + 2Al into the Mo–Si reaction systems facilitated self-sustaining combustion and contributed to in situ formation of MoSi2 and Al2O3. The samples adopting the former thermite reagent were more exothermic and produced composites with MoSi2/Al2O3 from 2.0 to 4.5, beyond which combustion failed to proceed. Because of lower exothermicity of the reactions, the final products with MoSi2/Al2O3 from 1.2 to 2.5 were fabricated from the SHS process involving the latter thermite mixture. Combustion temperatures of both reaction systems decreased from about 1640 to 1150 °C with increasing MoSi2/Al2O3 proportion, which led to a phase transition of MoSi2. It was found that the dominant silicide was β-MoSi2 when the combustion temperature of the synthesis reaction exceeded 1550 °C and shifted to α-MoSi2 as the combustion temperature fell below 1320 °C. The results of this study showed an energy-efficient fabrication route to tailor the phase and content of MoSi2 in the MoSi2–Al2O3 composite. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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