in the present work, the effect of ca(no3)2.4h2o and (nh4)2hpo4 primary solutions as the beginning materials in synthesis of a calcium phosphate phase, was examined. so, we investigated the wet chemical reactions in solution at different temperatures by a hydrothermal condition aimed at hydroxyapatite (ca10(po4)6(oh)2); (hap) synthesis. the powders were investigated by xrd,sem, fe-tem, hrtem, e...