Sinterability of Calcium Phosphate Through Rapid Sintering

Development of dense nanostructured hydroxyapatite (HA) with the major concern to enhance densification while limiting its grain growth has received great demand. This is due to inherent brittleness and lower mechanical strength of HA ceramic. A promising way to obtain this could be a fabrication of nanostructured HA materials through rapid sintering process. In this work, eggshell derived hydroxyapatite powder has been prepared via solid state route and its sinterability was investigated through microwave sintering (1000-1250 °C). The phase stability, microstructural evolution, relative density and hardness of the microwave sintered HA were reflected. The results indicate that the rapid sintering regime has been successfully employed with pure HA phase stability remained up to 1200°C and the relative density and hardness increase with increase in sintering temperature. On top of that, the result also showed good correlation of grain size and mechanical properties of HA and supported that microwave sintering did not promote extensive grain growth of HA. (paper)