Chapter 31. Ultrasonic and Vibration Characterization of Hybrid and Sandwich Carbon-Carbon Composites

  1. John B. Wachtman Jr
  1. U. K. Vaidya,
  2. H. Mahfuz and
  3. S. Jeelani

Published Online: 26 MAR 2008

DOI: 10.1002/9780470314715.ch31

Proceedings of the 19th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - A: Ceramic Engineering and Science Proceedings, Volume 16, Issue 4

Proceedings of the 19th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - A: Ceramic Engineering and Science Proceedings, Volume 16, Issue 4

How to Cite

Vaidya, U. K., Mahfuz, H. and Jeelani, S. (1995) Ultrasonic and Vibration Characterization of Hybrid and Sandwich Carbon-Carbon Composites, in Proceedings of the 19th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - A: Ceramic Engineering and Science Proceedings, Volume 16, Issue 4 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314715.ch31

Author Information

  1. Materials Research Laboratory Tuskegee University, Tuskegee, AL 36088

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1995

ISBN Information

Print ISBN: 9780470375372

Online ISBN: 9780470314715

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Keywords:

  • fabricated;
  • ultrasonic;
  • densificutiun;
  • vibration;
  • densification

Summary

Carbon/carbon (C/C) composites were developed on a conceptual level with a goal of developing low cost functional composites. C/C composite systems considered in this study are classified as hybrid and sandwich. These composites were fabricated from continuous woven carbon fabric in plain, eight harness satin (8HS) and stretch broken weave architectures in conjunction with nonwoven carbon mat reinforcement. In sandwich composites, the nonwoven mat was sandwiched between continuous fabric reinforcement; while in hybrid composites, the nonwoven mat was alternated with continuous reinforcement. Ultrasonic and vibration based nondestructive evaluation (NDE) of the hybrid and sandwich composite systems was conducted at three processing stages, namely; as-cured, after first carbonization and after first densification. Ultrasonic velocity measurements in the in-plane and through-the-thickness directions were found to be influenced by the evolving material microstructure and fabric architecture. Vibration damping of sandwich and hybrid composites was an order of magnitude higher than the conventional woven C/C composite systems. With regard to processing, the incorporation of nonwoven carbon mat in conjunction with continuous reinforcement enabled rapid infiltration during densification stage of processing for the sandwich and hybrid C/C composites.