真空等离子喷涂HA/Ta复合涂层

Vacuum Plasma Spray Hydroxyapatite/Tantalum Composite Coatings

羟基磷灰石(HA)具有良好的生物相容性和骨传导能力,采用等离子体喷涂技术在钛合金等金属基材上制备的HA涂层材料已在临床医学上被广泛使用。但是,HA涂层与钛合金基材之间较低的结合强度影响了植入物在体内的长期使用。本文采用真空等离子体技术制备钽(Ta)掺杂的HA涂层,以期在保持其良好生物学性能的同时提高其结合强度。HA/Ta复合涂层的微观形貌、元素组成和相组成由SEM及配套的能谱仪(EDS)和XRD分析技术表征。按ASTMC-633标准对涂层的结合强度进行了测试。将涂层试样浸泡于模拟体液中以评估其生物活性。结果表明:Ta增强HA涂层具有粗糙的表面和层状结构,其结合强度随着Ta含量的增加而增加。掺60%Ta(H4T6)涂层的结合强度达到37.2MPa,约为HA涂层的1.9倍。模拟体液浸泡试验显示,掺钽HA涂层表面形成了类骨磷灰石,表明具有良好的生物活性。

Plasma sprayed hydroxyapatite （HA） coating on titanium alloy substrate have been used extensively due to their excellent biocompatibility and osteoconductivity. However, the low bond strength between HA and Ti alloy is still problematic in the long-term implantation lifespan. In this paper, HA coatings with various Ta contents were fabricated by vacuum plasma spraying （VPS）. The microstructure, chemical compositions and phase composition of the coatings were characterized by scanning electron microscopy （SEM） with an energy dispersive spectroscopy and X-ray diffraction （XRD）. The coatings had a rough surface and lamellar structure including some pores. ASTM C-633 standard was used for the measurement of the bonding strength, which increased with increase of Ta contents in the composite coatings. The bonding strength of coating containing 60% Ta （H4T6） reached to about 37.2 MPa, was about 1.9 times higher than that of HA coating. In vitro bioactivity evaluated in simulated body fluids （SBF） results show that bonelike apatite layer was formed on the coatings surface, which indicated the good bioactivity for the Ta reinforced HA coatings and a potential candidate in implant surface modification.