几种阳离子置换磷酸钙生物陶瓷的XRD分析

XRD ANALYSIS OF SEVERAL CATION-SUBSTITUTED CALCIUM PHOSPHATE BIOCERAMICS

磷酸钙生物陶瓷中存在阳离子置换现象 .对可吸收Ca2 NaK(PO4) 2 陶瓷、湿法合成的含锶和含镧羟基磷灰石进行X射线衍射 (XRD)分析发现 :Ca2 NaK(PO4) 2 可看作Na+ 在KCaPO4中的固溶体 ,其衍射角位于KCaPO4和NaCaPO4之间 ;含锶羟基磷灰石的衍射峰向低角度偏移 ,峰宽而弱 ,其热稳定性变差 ,分解出磷酸三钙和氧化钙 ;相同配料下含镧羟基磷灰石的衍射峰的宽化和弱化更严重 ,其热稳定性更差 .

Cation substitution exists in calcium phosphate bioceramics. X -ray diffraction(XRD) method is utilized to analyze the absorbable Ca 2NaK(PO 4) 2 ceramic, the strontium_containing and lanthanum_containing hydroxyapatite(HA)synthesized by wet method. Ca 2NaK(PO 4) 2 may be considered as a solid solution of Na + in KCaPO 4,and its diffraction angles lie between KCaPO 4 and NaCaPO 4. Strontium in HA decreases the diffraction angles, and broadens and weakens the diffraction peaks of HA. It also decreases the thermal stability of HA, which deco_mposes into tricalcium phosphate and calcium oxide. As for lanthanum_containing HA at the same addition ratio, the broadening and weakening of the diffraction peaks of hydroxyapatite are more significant, and the thermal stability is even worse.