Journal of Materials Science

, Volume 26, Issue 5, pp 1333–1345

Conversion mechanisms of a polycarbosilane precursor into an SiC-based ceramic material

Authors

  • E. Bouillon
    • Laboratoire de Chimie du Solide du CNRSUniversité de Bordeaux 1
  • F. Langlais
    • Laboratoire de Chimie du Solide du CNRSUniversité de Bordeaux 1
  • R. Pailler
    • Laboratoire de Chimie du Solide du CNRSUniversité de Bordeaux 1
  • R. Naslain
    • Laboratoire de Chimie du Solide du CNRSUniversité de Bordeaux 1
  • F. Cruege
    • Laboratoire de Spectroscopie Moléculaire et CristallineUniversité de Bordeaux 1
  • P. V. Huong
    • Laboratoire de Spectroscopie Moléculaire et CristallineUniversité de Bordeaux 1
  • J. C. Sarthou
    • Centre d'Etudes Scientifiques et Techniques d'AquitaineCEA
  • A. Delpuech
    • Centre d'Etudes Scientifiques et Techniques d'AquitaineCEA
  • C. Laffon
    • LURE, Bt 209DUniversité de Paris-Orsay
  • P. Lagarde
    • LURE, Bt 209DUniversité de Paris-Orsay
  • M. Monthioux
    • Laboratoire Marcel MathieuUniversité de Pau
  • A. Oberlin
    • Laboratoire Marcel MathieuUniversité de Pau
Papers

DOI: 10.1007/BF00544474

Cite this article as:
Bouillon, E., Langlais, F., Pailler, R. et al. J Mater Sci (1991) 26: 1333. doi:10.1007/BF00544474

Abstract

The pyrolysis of a PCS precursor has been studied up to 1600 °C through the analysis of the gas phase and the characterization of the solid residue by thermogravimetric analysis, extended X-ray absorption fine structure, electron spectrocopy for chemical analysis, transmission electron microscopy, X-ray diffraction, Raman and Auger electron spectroscopy microanalyses, as well as electrical conductivity measurements. The pyrolysis mechanism involves three main steps: (1) an organometallic mineral transition (550 < Tp < 800 °C) leading to an amorphous hydrogenated solid built on tetrahedral SiC, Si02 and silicon oxycarbide entities, (2) a nucleation of SiC (1000 < Tp < 1200 °C) resulting in SiC nuclei (less than 3 nm in size) surrounded with aromatic carbon layers, and (3) a SiC grain-size coarsening (Tp > 1400 °C) consuming the residual amorphous phases and giving rise simultaneously to a probable evolution of SiO and CO. The formation of free carbon results in a sharp insulator-quasimetal transition with a percolation effect.

Copyright information

© Chapman and Hall Ltd. 1991