Elsevier

Carbon

Volume 27, Issue 5, 1989, Pages 697-707
Carbon

Pitch-based processing of carbon-carbon composites

https://doi.org/10.1016/0008-6223(89)90203-0Get rights and content

Abstract

A microstructural approach was used to study the process mechanisms limiting the efficiency of pitch-based composite fabrication, which should have advantages of low cost and high carbon yield with a graphitizable matrix. The microstructural framework is established by mesophase mechanisms active in the final stages of liquid phase pyrolysis. The formation of mesophase in fiber bundles and 3D preforms, for various fibers and pitches, and as affected by pressure, displayed common patterns of wetting, mesophase alignment on fiber substrates, and disclination structures. Mesophase bloating by pyrolysis gases can expel matrix from the preform, and the need was seen for a means to fix the mesophase in place before carbonization. An oxidation process, similar to that used in the stabilization of mesophase fiber, was found to be applicable in depth to mesophase-impregnated preforms because a network of access porosity in the matrix results from the mismatch of thermal expansivities of fiber and mesophase. The successful application of oxidation processing to 2D preforms, which are particularly vulnerable to bloating in the direction lacking reinforcement, showed that high-pressure carbonization is not required for pitch-based processing. With a method for matrix stabilization in hand, process development may turn to use of the flow capability of mesophase pitch to impregnate the fiber preform.

References (27)

  • E. Fitzer

    Carbon

    (1987)
  • J.L. White

    Prog. Solid-State Chem.

    (1975)
  • J.E. Zimmer et al.

    Advances in Liquid Crystals

    (1982)
  • J.E. Zimmer et al.

    Carbon

    (1983)
  • J.E. Zimmer et al.

    Carbon

    (1988)
  • V.A. Weinberg et al.

    Fuel

    (1983)
  • J. Jortner

    Carbon

    (1986)
  • J. Dubois et al.

    Metallography

    (1970)
  • H. Brückmann
  • L.E. McAllister et al.
  • J.D. Brooks et al.

    Chem. & Phys. Carbon

    (1968)
  • J.L. White et al.
  • J.L. White et al.
  • Cited by (92)

    • Carbon Based Materials

      2021, Encyclopedia of Materials: Metals and Alloys
    • Enhanced thermo-mechanical and electrical properties of carbon-carbon composites using human hair derived carbon powder as reinforcing filler

      2018, Advanced Powder Technology
      Citation Excerpt :

      This densification process is generally done either by repeated resin impregnation followed by carbonization of the precursor polymer composites or by gas phase CVI of precursor composite. These processes are very time consuming and also involve huge capital investment and required technical expertise, which limit their application mainly in defence and aerospace sector [11–13]. In order to amplify the scope of applications of CCs, some of the research groups have concentrated their research work on cost reduction of the CCs by modification in the formulations/raw materials compositions used in the manufacture of the precursor polymer composites.

    View all citing articles on Scopus
    View full text