水热电化学法制备HA/ZrO_2复合涂层

HA/ZrO_2 Composite Coating Prepared by Hydrothermal- Electrochemical Method

采用水热电化学法成功制备了HA/ZrO2复合涂层,对涂层的组分结构、表面形貌、热稳定性进行了研究,并探讨了ZrO2的复合对涂层结合强度和生物活性的影响。结果表明:当温度小于200℃时,得到缺钙磷灰石Ca10-x(HPO4)x(PO4)6-x(OH)2-x(calciumdeficienthydroxyapatite,简称CDHA,0≤x≤1)和ZrO2的复合涂层,温度在200℃时,得到HA/ZrO2复合涂层;经焙烧处理后,涂层中四方晶相ZrO2(t-ZrO2)与单斜晶相ZrO2(m-ZrO2)之间发生马氏体相变;800℃焙烧后,HA部分分解为β-Ca3(PO4)2(β-TCP);当涂层中ZrO2小于35.22%(质量分数,下同)时,HA/ZrO2复合涂层的结合强度明显高于纯HA涂层;复合涂层在模拟体液中浸泡7d后,表面即形成一层碳磷灰石层,ZrO2的复合没有降低涂层的生物活性。

HA/ZrO2 composite coatings were successfully prepared on titanium electrode using the hydrothermal-electrochemical method via adding ZrO2 powder in the electrolyte in an autoclave, and the component, the structure, the surface morphology and the thermal stability of composite coatings were studied. The effect of ZrO2 recombination on the bonding strength and bioactive properties of composite coatings were investigated. The results show that the composite coatings consist of calcium-deficient hydroxyapatite （Ca10-x（HPO4）x（PO4）6-x（OH）2-x, 0≤x≤1 ） and ZrO2 when temperature below 200℃, and HA/ZrO2 composite coatings were obtained when temperature controlled at 200℃. Tetragonal phase ZrO2 （t-ZrO2） undergo a martensitic transformation to the monoclinic phase ZrO2 （m-ZrO2） after calcinated treatment. When calcinated temperature above 800℃, HA partially decomposed to β-calcium phosphate（fl-TCP）. The bonding strength of HA/ZrO2 composite coating obviously higher than that of pure HA coating when ZrO2 below 35.22wt%. HA/ZrO2 composite coating surface were covered by carbonate hydroxyapatite coating after immersion in simulate body fluid for 7 days, which indicated that the ZrO2 adding in HA coating improved the bonding strength and didn＇t decrease the bioactive properties of the coating.