Microstructural and mechanical characterisation of biomorphic SiC ceramics synthesised from coir fibreboard preform

摘要

Fibreboards made of coir fibres were converted to carbon templates by controlled thermal processing and were further infiltrated and reacted with liquid Si at 1550 ℃ under vacuum to produce biomorphic SiC ceramics. Microstructural analysis including quantitative characterisation of microstructure was undertaken, employing optical microscopy, scanning electron microscopy and X-ray diffraction techniques. Mechanical properties were investigated at room temperature. Testing included measure-ment of flexural strength and elastic modulus by the three-point bending method and fracture toughness by the single edge notched beam technique. Properties measured on this material are typical of the biomorphic ceramics made from the natural and artificial (processed) bio-precursors.