Electrical properties of biomorphic SiC ceramics and SiC/Si composites fabricated from medium density fiberboard
A study has been made of the dependences of the electrical resistivity and the Hall coefficient on the temperature in the range 1.8-1300K and on magnetic fields of up to 28kOe for the biomorphic SiC/Si (MDF-SiC/Si) composite and biomorphic porous SiC (MDF-SiC) based upon artificial cellulosic precur...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2011 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/62073 |
| Acceso en línea: | http://hdl.handle.net/10261/62073 |
| Access Level: | acceso abierto |
| Sumario: | A study has been made of the dependences of the electrical resistivity and the Hall coefficient on the temperature in the range 1.8-1300K and on magnetic fields of up to 28kOe for the biomorphic SiC/Si (MDF-SiC/Si) composite and biomorphic porous SiC (MDF-SiC) based upon artificial cellulosic precursor (MDF - medium density fiberboards). It has been shown that electric transport in MDF-SiC is effected by carriers of n-type with a high concentration of ∿1020cm-3 and a low mobility of ∿0.4cm2V-1s-1. The specific features in the conductivity of MDF-SiC are explained by quantum effects arising in disordered systems and requiring quantum corrections to conductivity. The TEM studies confirmed the presence of disordering structural features (nanocrystalline regions) in MDF-SiC. The conductivity of MDF-SiC/Si composite originates primarily from Si component in the temperature range 1.8-500K and since ∿500 to 600K the contribution of MDF-SiC matrix becomes dominant. © 2010 Elsevier Ltd. |
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