Abstract：
Porous Nb-25Ta-25Ti alloys (60% porosity and 100-600 μm pore size) for bone implant applications were manufactured combining impregnation and sintering methods. Surfaces with porous micro-nanostructured networks on Nb-Ta-Ti alloys were successfully modified by various surface pre-treatments (acid etching, alkali-heat treatment and annealing treatment). Surface characteristics and Ca-P layer deposition behaviors of the multilevel structured porous Nb-Ta-Ti alloys were investigated by conducting various tests, including x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray, atomic force microscopy and optical contact angle measurement. In particular, bulk Nb-Ta-Ti alloys were also used as mutual control. The results demonstrated that the porous alloy exhibited a unique multilevel porous structure with macro-networks and micro-pits after pre-treatments. The surface passive TiO2/Nb2O5/Ta2O5layers on Nb-Ta-Ti alloys were partially dissolved by the corrosive attack of hydroxyl ions during alkali heat treatment. In addition, subsequent annealing treatment increased the density of the gel layers formed during alkali heat treatment. After immersion in SBF for 14 d, a continuous relatively uniform apatite layer was formed on the multilevel structured surfaces. Moreover, the mechanism of surface mineralization can be construed as electrostatic interactions between substrates and ions. Furthermore,in vitrocell culture showed that Nb-Ta-Ti alloys had a good biocompatibility and the multilevel porous structure could enhance the cellular behaviors including: cell adhesion and spreading.
摘要：
结合浸渍和烧结方法制造了用于骨植入物应用的多孔Nb-25Ta-25Ti合金（60％的孔隙率和100-600μm的孔径）。通过各种表面预处理（酸蚀刻，碱热处理和退火处理)。通过各种试验研究了多层多孔Nb-Ta-Ti合金的表面特性和Ca-P层沉积行为。包括X射线衍射，扫描电子显微镜，能量色散X射线，原子力显微镜和光学接触角测量。特别是,块状Nb-Ta-Ti合金也被用作相互控制。结果表明，多孔合金在预处理后表现出独特的多级多孔结构，具有宏观网络和微坑。Nb-Ta-Ti合金上的表面钝化TiO2/Nb2O5/Ta2O5层在碱热处理过程中被羟基离子的腐蚀侵蚀部分溶解。此外,随后的退火处理增加了在碱热处理期间形成的凝胶层的密度。在SBF中浸泡14d后，在多级结构表面上形成连续的相对均匀的磷灰石层。此外，表面矿化的机制可以解释为底物与离子之间的静电相互作用。此外，体外细胞培养表明，Nb-Ta-Ti合金具有良好的生物相容性，多级多孔结构可以增强细胞粘附和铺展行为。
