Abstract
Changes in the microstructure of single-crystal apatite fibres as a result of heat treatment were examined using a range of techniques: XRD, FT-IR, SEM and TEM. The as-synthesized fibres were highly strained and comprised domains that were preferentially oriented with the c-axis parallel to the surface of the substrate. When the apatite fibres were heated at 800°C to 1200°C for 1 h, the domain structure disappeared but remained highly strained. The ultrastructure of fibres heated at 1000°C and 1200°C changed during sintering to form some grain boundaries and dislocations. The apatite fibres heated at 1200°C for 1 h contained many voids formed by the release of carbonate groups during sintering.
