Characterisation of Carbon Fibre Kaolin Matrix Composites
Although structural kaolin based ceramics are attractive and useful materials, having good mechanical characteristics, low density, good corrosion and high temperature resistance, their use is restricted by their brittle behaviour. In order to improve their properties and mainly strength, toughness and high temperature performance, fibre composite ceramics have been developed. In the present work a series of kaolin-short random dispersed Grafil carbon fibre composites were produced and sintered in an inert atmosphere of Argon at 1000oC and 1300oC and characterised using various techniques. XRD analysis of the kaolin matrix at 1000oC showed that the crystalline phases were decomposed without the formation of mullite a fact which also reconfirmed by SEM examination. However at 1300oC mullite formation was well evidenced. XRD analysis of the fibres in “as received” showed that they have graphite structure which was also retained, as SEM examination revealed, after sintering. Examination of the Grafil fibres showed that they were quite uniform in length and diameter and retained their integrity after sintering at the examined temperatures. Examination the fractured composite surfaces showed only a weak bond between fibres and matrix and at the pull out areas the fibres were replicated in the matrix.
S. Papargyri et al., "Characterisation of Carbon Fibre Kaolin Matrix Composites", Advances in Science and Technology, Vol. 45, pp. 1450-1455, 2006