| Autor: |
Tetsuo Yamada, Takeshi Suemasu, Yasuhiko Kohtoku, Yoshizumi Tanaka |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
Ceramic Microstructures ISBN: 9781461374626 |
| DOI: |
10.1007/978-1-4615-5393-9_56 |
| Popis: |
Ultrafine SiC and Si/C/N powders were prepared by photochemical reactions of SiH4, C2H4 and NH3 under dual irradiation of CO2 and excimer laser beams. Effects of process variables on the characteristics of these powders were studied. Enhanced crystallization and size reduction of SiC particles were observed by irradiation of excimer laser. Growth of the particles proceeded by CO2 laser irradiation, whereas refinement of the particles occurred by ablation of the initially formed particles under excimer laser irradiation. Uniformly mixed state of silicon, carbon and nitrogen atoms in the Si/C/N composite particles was confirmed by transition electron microscopy and x-ray photoelectron spectroscopy analyses. Sintering behavior of the Si/C/N powders was examined by microwave sintering and conventional hot-pressing, and the resultant Si3N4-SiC composites were consolidated into highly dense bodies with fine grain size and high hardness. It was found that the vapor- phase reaction using dual-type CO2 and excimer lasers offered a feasible method for controlling composition, crystallinity and particle size in the synthesis of ultrafine sinterable single- and multi-component powders |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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