钛基多孔HA/SiO2复合涂层的制备及性能研究

为了制得表面多孔且与基材结合强度高的羟基磷灰石(HA)涂层,实验中以正丁醇为分散介质,以SiO2粉末为添加剂,纯钛片为基材,电泳沉积制备羟基磷灰石/二氧化硅/壳聚糖/(HA/SiO2/CS)复合涂层,经后续热处理得到多孔HA/SiO2复合涂层,采用扫描电镜(SEM)、傅立叶红外光谱仪(FT-IR)、X射线衍射仪(XRD)、万能材料试验机对涂层的表面形貌、组成、结构和结合强度进行测试和表征,并通过模拟体液(SBF)浸泡法对复合涂层的生物活性进行评价.结果表明:当悬浮液中的HA/SiO2/CS质量比为1∶1∶1时,制得的HA/SiO2/CS涂层经700℃热处理后获得的HA/SiO2复合涂层孔洞分布均匀,大孔孔径在10～15μm,小孔孔径在1～5μm;涂层与基材的结合强度达到25.5 MPa;多孔HA/SiO2复合涂层在SBF中浸泡7 d后,涂层表面碳磷灰石化;说明实验中添加SiO2所制得的多孔HA/SiO2复合涂层与钛基材结合强度高,且具有良好的生物活性.

Study on Fabrication and Properties of Porous HA/SiO2 Composite Coating on Titanium Substrate

In order to obtain porous hydroxyapatite(HA) coating with high bonding strength to substrate,hydroxyapatite/silica/chitosan(HA/SiO2/CS) composite coatings were prepared on titanium substrate by electrophoretic deposition(EPD) in n-butylalcohol as dispersion medium and SiO2 powder as additive.And then a porous HA/SiO2 composite coating was obtained by sequentially sintering treatment.The surface morphology,chemical composition,phase composition and the bonding strength between composite coating and substrate were characterized by scanning electron microscopy(SEM),fourier transform infrared spectrometer(FT-IR),X-ray diffraction(XRD) and shear strength testing experiment,respectively.The bioactivity of the porous HA/SiO2 composite coating was evaluated by immersion in simulated body fluid(SBF).The results showed that the porous HA/SiO2 composite coating with uniform cavities was obtained by sintering at 700 ℃ from the HA/SiO2/CS composite coating fabricated by EPD in suspension with 1∶1∶1 mass ratio of HA/SiO2/CS.The large-pore diameter was about 10～15 μm,the small-pore diameter was about 1～5 μm,and the bonding strength between composite coating and substrate was up to 25.5 MPa.The coating surface was covered totally by carbonate-apatite after immersion in SBF for 7 d.This porous HA/SiO2 composite coating exhibits a good bioactivity and high bonding strength between composite coating and substrate.