J Mater Sci Technol ›› 2009, Vol. 25 ›› Issue (02): 251-253.

• Articles • Previous Articles     Next Articles

Influence of Thermal Shock on the Mechanical Behavior of Si-SiC Coated Carbon/Carbon Composites

Qiangang Fu, Hejun Li, Yongjie Wang, Kezhi Li and Lu Wei   

  1. C/C Composites Research Center, Northwestern Polytechnical University, Xi0an 710072, China
  • Received:2008-06-20 Revised:2008-09-01 Online:2009-03-28 Published:2009-10-10
  • Contact: Hejun Li
  • Supported by:

    the National Natural Science Foundation of China under grant Nos. 50802075 and 90716024,
    the “111” Project, China under grant No. 08040

Abstract:

Si-SiC coating was prepared on the surface of carbon/carbon (C/C) composites by a two-step technique of pack cementation, and the influences of thermal shock between 1773 K and room temperature in air on the mechanical property and fracture behavior of the coated C/C were studied. The results show that, after thermal shock between 1773 K and room temperature for 5, 10 and 15 times, the flexural strength of coated composites increases by 4.29%, 15.00% and 24.20%, respectively. The toughness of the coated C/C enhances gradually during the thermal shock test. The improvement of the mechanical property after the thermal shock test is primarily caused by the weakening of the fiber-matrix interface and the reduction of residual thermal stresses by thermal shock.

Key words: Carbon/carbon composites, Coating, Mechanical behavior