B(4)C coated carbon fibre reinforced Si(3)N(4)
The quality of long, pitch-based carbon fibre reinforced Si(3)N(4) composites prepared by slurry infiltration and hot-pressing were assessed from mechanical properties combined with acoustic emission. Typical room temperature load vs. deflection curves were measured. Macro- and microstructural observations with optical microscopy, X-ray powder diffraction and scanning transmission and high resolution electron microscopy are presented. The amount of alpha to beta transformation of the Si(3)N(4) matrix, and the amount of SiC as reaction product were determined by XPD. The composition of the interfacial crack surfaces were analysed by energy dispersive X-ray parallel electron energy loss spectroscopy. The results were focused on composites reinforced with carbon fibres precoated with a B(4)C and a Cpyr/B(4) coating. The effects of such coatings on the load transfer at the fibre/matrix interface are discussed. Composites with B(4)C coated fibres exhibit a higher crack toughness, with some reduction in strength, than composites with uncoated fibres or Cpyr/B(4)C coated fibres.
Bibliographic Reference: Paper presented: Conference on Composites, Advanced Ceramics, Materials and Structures, Cocoa Beach (US), January 7-11, 1996
Availability: Available from (1) as Paper EN 40006 ORA
Record Number: 199611045 / Last updated on: 1996-09-30
Original language: en
Available languages: en