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利用液相沉淀法研究了ｐＨ为１０～１１时，［Ｃａ~（２－）］浓度大于０．５ｍｏｌ／Ｌ条件下羟基磷灰石（ＨＡＰ）的生成机理及其动力学。结果表明反应经历了从磷酸八钙很快转化为非晶态磷酸钙（ＡＣＰ），继而转化为缺钙羟基磷酸石和羟基磷灰石的过程。缺钙羟基ＡＣＰ磷灰石是向羟基磷灰石转化的非化学计量物质。温度对转化反应速率影响很大，在２５℃时生成纯ＨＡＰ需要２５ｈ，而在６０℃时只须５ｍｉｎ。ＡＣＰ向ＨＡＰ的转化反应为二级反应，活化能为９５ｋＪ／ｍｏｌ，由此推测此反应为表面控制反应。
The formation mechanism and kinetics of hydroxyapatite (HAP) at [Ca ~ (2-)]> 0.5mol / L were studied by liquid-phase precipitation at pH 10-11. The results show that the reaction has undergone a rapid conversion from octacalcium phosphate to amorphous calcium phosphate (ACP) which in turn converts to calcium-deficient hydroxyphosphate and hydroxyapatite. Calcium-deficient hydroxy-ACP apatite is a non-stoichiometric substance that is converted to hydroxyapatite. Temperature has a significant effect on the conversion reaction rate, which takes 25 h to generate pure HAP at 25 ° C and only 5 min at 60 ° C. The conversion of ACP to HAP is the second-order reaction with an activation energy of 95 kJ / mol, suggesting that this reaction is a surface-controlled reaction.