Bulk Structures Using Hydroxyapatite Nanocrystals

To date, few reports are available on the effect of the powders properties such as particle size, distribution, density and morphology on the densification behavior and the mechanical and microstructural characteristics of those powder compacts [33, 125-128]. In order to study the aspect ratio effect on densification, high-aspect ratio nanopowder or rod-shaped particles (aspect ratio 7.2) and low-aspect ratio or spherical nanopowders (aspect ratio 1.3 0.3) were synthesized using an emulsion technique with different parameters [103]. The specific average surface areas of the as-synthesized spherical and rod-shaped HA powders were 39and 29m g , 

In all cases, the sintered microstructure did not show any rod-shaped particles in the final structure of these nanopowders due to grain growth. 

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