在120 ℃的条件下，利用硼酸和石灰进行水热反应制备五水合六硼酸钙（CaB6O10·5H2O）。五水合六硼酸钙的差热分析结果显示，其脱水分4步，在800 ℃和900 ℃附近分别有一个相变放热峰和吸热峰。对五水合六硼酸钙的高温相变行为进行了探讨，化学分析、XRD、TG-DTA 和IR分析结果表明：在600 ℃时，首先发生晶态的五水合六硼酸钙向非晶态的无水六硼酸钙（CaB6O10）转化，至800 ℃时无定型的无水六硼酸钙转变为晶态的无水六硼酸钙，进一步升温至900 ℃时无水六硼酸钙分解为晶态的四硼酸钙（CaB4O7）和玻璃态的三氧化二硼。

CaB6O10·5H2O was synthesized by hydrothermal method at 120 ℃ with using boric acid and lime as materials.The thermal analysis of CaB6O10·5H2O showed that CaB6O10·5H2O was dehydrated by 4 steps，one exothermic peak near 800 ℃ and one endothermic peak near 900 ℃ were found，respectively.The high temperature phase transition behavior of CaB6O10·5H2O was discussed by chemical analysis，XRD，TG-DTA and IR analysis.The results indicated that：the first crystalline CaB6O10·5H2O was converted to amorphous CaB6O10 at 600 ℃，and the amorphous CaB6O10 was converted to crystalline CaB6O10 at 800 ℃，and finally CaB4O7 and vitreous B2O3 were obtained by the decomposition of crystalline CaB6O10 at 900 ℃.