Ti6Al4V表面激光熔覆生物陶瓷复合涂层研究

Investigation of Bioceramic Composite Coatings Fabricated by Laser Cladding on Ti6Al4V Surface

针对Ti6Al4V合金在作为医用植入体中存在耐磨性及生物活性差的问题,采用激光熔覆制备表面羟基磷灰石HA/TC4复合生物陶瓷涂层。综合利用基体的力学性能和涂层的生物性能,具有显著优势。通过设计复合涂层的成分配比和优化激光加工工艺参数,在Ti6Al4V合金表面制备了成型良好、无冶金缺陷的单道和多道搭接生物复合涂层。对表面复合涂层的微观组织及性能进行了研究,结果表明涂层中生成了α-Ti、Ti3P、Ti O、Ca Ti O3和β-Ca3(PO4)2等相。涂层的摩擦系数低于基体,磨痕宽度小于基体,表明复合涂层具有优良的耐磨特性。模拟体液在涂层表面的接触角小于在钛基体表面接触角,表明激光熔覆涂层改善了基体的表面润湿性。

To improve the wear resistance property and bioactivity of Ti6A14V alloy which is utilized as implant in medical application, the composite coating of Hydroxyapatite （HA）/TC4 is fabricated on the surface of Ti6A14V alloy by laser cladding. This process has shown distinctive advantages due to combination the mechanical property of metal substrate and the biological property of ceramic coating. Through optimizing the ratio of HA/TC4 composite and laser cladding parameters, ideal single layer and multiple layer overlapped bioceramic composite coating is fabricated without metallic defects. The composite coating contains phases such as α-Ti, Ti3P, TiO, biocompatible ceramic phases as CaTiO3 and β -Ca3（PO02. The width of wear track of composite coating is lower than that of the substrate, which indicate that the wear resistance of Ti6A14V alloy is significantly improved. The contact angle of simulated body fluid （SBF） against coating is smaller than that against the titanium substrate, which indicate that the wettability is improved by laser cladding coating.