生物玻璃的烧结与析晶

利用玻璃的烧结收缩,结合差热分析和X射线衍射分析,研究了CaO-SjO_2-P_2O_5系统生物玻璃的烧结和析晶动力学。确定它的烧结机制主要是粘性流动烧结。A玻璃和Ⅰ-2玻璃的烧结活化能分别为540kJ/mol和476kJ/mol。析晶相是磷灰石和硅灰石。A玻璃和Ⅰ-2玻璃的析晶表观活化能分别约为480kJ/mol和390kJ/mol。通过分析烧结温度、Na_2O含量对烧结和析晶的影响,选择了合适的烧结条件,控制烧结和析晶程度,获得了既有足够的自身强度,又有一定的结合强度的多孔玻璃陶瓷。

SINTERING AND DEVITRIFCATION OF BIOGLASS

Sintering kinetics, crystallization phases and crystallization kinetics of bioglass in the system of CaO- SiO_2-P_2O_5 were studied by measuring the sintering shrinkage of glass powder compacts, combined with DTA and X-ray diffraction analysis. It is found that the sintering of bioglass is mainly of viscous flow mechanism. The activation energy of the sintering of glass A and 1-2 is 540 kJ/mol and 476kJ/mol respectively. The devitrification phases are apatite and wollastonite. The apparent activation energy of crystallization of glass A and 1-2 is about 480 kJ/mol and 390 kJ/mol respectively. By analysing the effect of sintering temperature and Na_2O content on sintering and crystallization, sintering condition for bioglass can be optimized.