等离子喷涂-水热处理制备二氧化钛-羟基磷灰石复合涂层

TITANIA-HYDROXYAPATITE COMPOSITE COATING PREPARED BY PLASMA SPRAY-HYDROTHERMAL TREATMENT

为克服等离子喷涂羟基磷灰石生物涂层在结合强度和成分上的缺点 ,通过在钛合金基体上等离子喷涂二水磷酸氢钙和二氧化钛 (锐钛矿型 )复合粉末 ,并后续水热处理 ,制备了二氧化钛 -羟基磷灰石复合涂层。结果表明 :二水磷酸氢钙和二氧化钛复合粉末的等离子喷涂涂层由CaHPO4,Ca2 P2 O7,Ca3(PO4) 2 ,非晶磷酸钙和二氧化钛组成。水热处理涂层由羟基磷灰石和二氧化钛组成 ,升高水热处理温度可提高涂层中羟基磷灰石的结晶性。随着原始粉中二氧化钛加入量的增加 ,喷涂涂层中磷酸钙的含量和水热处理涂层中羟基磷灰石的含量减少 ,羟基磷灰石的晶体形貌从细针状变为小颗粒状 ,喷涂涂层和水热处理涂层的结合强度也随之升高。当二氧化钛的质量分数为 60 % ,水热处理涂层的结合强度可达

In the view of overcoming the disadvantages of plasma sprayed hydroxyapatite coating in bonding strength and chemical composition, titania_hydroxyapatite composite coating was prepared by plasma spraying CaHPO_4·2H_2O (DCPD) and titania mixed powder on titanium alloy substrate and subsequently hydrothermal treating the as_sprayed coating. It is found that the plasma sprayed coating from DCPD and titania mixture consists of CaHPO_4, Ca_2P_2O_7, Ca_3(PO_4)_2, amorphous calcium phosphate and titania, but after hydrothermal treatment coating is composed of hydroxyapatite and titania. The crystallinity of hydroxyapatite increases with the increase of temperature of hydrothermal treatment. The content of calcium phosphate in the as_sprayed coating and the content of hydroxyapatite in the hydrothermally treated coating increase with the increase of mass fraction of titania in the original mixed powder. The morphology of hydroxyapatite crystals varies from needle_like shape to fine particle shape and the bonding strength of the as_sprayed coating and the hydrothermally treated coating increases with the increase of mass fraction of titania in the original powder. The bonding strength of the hydrothermally treated coating becomes 17 MPa when the mass fraction of titania is 60% in the original powder.