Nanorod hydroxyapatite powders were synthesized using H3PO4 and Ca(OH)2 as precursor materials via a combination of chemical precipitation and microwave techniques route. Effects of various reactive solvent, heating mode of microwave and microwave time on phase stability and morphology of as-prepared hydroxyapatite were investigated based on orthogonal design. The results suggested that when the reactive solvent was pure water, uniform, no agglomerated rod-like hydroxyapatite was formed. Increasing microwave time improved the crystallinity and morphology of rod-like hydroxyapatite, significantly. Heating mode of microwave had a profound influence on the shape, dispersibility and morphology of nanorod hydroxyapatite. Continuously heating by microwave was better for synthesis of nanorod hydroxyapatite. Phase stability of high energy metastable hydroxyapatite brought by microwave route was improved by low temperature presintering.

Keywords: Hydroxyapatite, Rod, Microwave route, Phase stability.