SINTERING OF HYDROXYAPATITE CERAMIC PRODUCED BY WET CHEMICAL METHOD

摘要

In the present work, densification of synthesised hydroxyapatite (HA) bioceramic prepared via chemical precipitation method was investigated. HA samples was prepared by compaction at 200 MPa and sintered at temperatures ranging from 800 deg C to 1400 deg C. The results revealed that the HA phase was stable for up to sintering temperature of 1250 deg C. However, decomposition of HA was observed in samples sintered at 1300 deg C with the formation of tetra-calcium phosphate (TTCP) and CaO. Samples sintered above 1400 deg C were found to melt into glassy phases. The bulk density increases with increasing temperature and attained a maximum value of 3.14 gcm-3 at 1150 deg C whereas maximum hardness value of 6.64 GPa was measured in HA sintered at 1050 deg C. These results are discussed in terms of the role of grain size.