HA粉末与烧结体的高温分解及再生特性

Investigation on High-temperature Decomposition and Regeneration Characteristics of Both Hydroxyapatite Powder and Sinters

采用高温DSC、Raman、XRD研究了HA粉末及烧结体的高温分解行为并探索其可再生性。结果显示,沉淀法制备的纳米HA粉末在1000℃开始分解,脱去羟基;温度高于1360℃时完全分解成β-磷酸三钙(β-TCP)和磷酸四钙(TTCP),在1450℃时β-TCP转变为α-TCP。高温煅烧后的HA粉末在慢冷过程中羟基部分再生,而其烧结体则未见回复。1 500℃高温烧结后的块体在CO2和H2O气氛中经900℃处理后,其表面发生了部分再生。HA的高温分解和再生性研究对其应用具有较高的实际指导价值。

X-ray diffractometer（XRD）,high-temperature raman spectroscopy,high-temperature differential scanning calorimeter（DSC） were used to investigate their decomposition characteristics of both hydroxyapatite powder and sinters,also their regeneration characteristics were explored.Results showed that nano HA powder prepared by the precipitation method gradually released its OH-ions from 1 000 ℃.When the heating temperature was higher than 1 360 ℃,HA decomposed into β-tricalcium phosphate（β-TCP） and tetracalcium phosphate（TTCP）.β-TCP changed into α-TCP at about 1 450 ℃.It was found that the decomposed powder regenerate to HA again under a slow cooling rate and in air atmosphere,and yet no any regeneration phenomenon was found in the decomposed sinters.When the decomposed sinters which was sintered at 1 500 ℃ were heat treated at 900 ℃ in CO2 and H2O atmosphere,the regeneration of HA was partly found on the surface of the sinters.There is high significance of investigating on the decomposition and regeneration characteristics of HA for its application.