Titanium Alloy-based Artificial Implant Surface Design And Manufacturing Research

Biocompatibility including physical compatibility and interface compatibility is the basic functional requirement for artificial implants. It is hard to insure the physical compatibility and interface compatibility of the implants at the same time by constructing them using single kind of biomaterial. Thus the surface design researches of the implants based on the differences of their functional requirements and physiological environments are very important. To improve the long-term biocompatibility and mechanical stability of Titanium alloy hard tissue and stent implants, the surface design and preparation researches have been carried out by combining the theoretical and experimental research methods. The contents and the results of this work are as follows:(1) The basic theory researches on the surface design of artificial implants. Summarized four kinds of artificial implants surface design methods based on the related theories of biomaterial surface engineering. By using them and considering the differences of the implants'functional requirements and physiological environments, proposed several feasible surface design methods for Titanium alloy hard tissue and stent implants. This work has specified the research direction for the experimental researches.(2) The preparation and characteristics researches of micro/nano structured composite bioceramic coatings on Titanium alloy. Using bioactive and gradient design methods of Titanium alloy hard tissue implants, two kinds of composite bioceramic coatings (SCS+T, SCS+HA) with certain micro/nano structure have been prepared on TC4 by combining biomimetic method and sol–gel process. The morphology, phases and tribological properties of the target coatings have been characterized and evaluated. The results indicate that the two kinds of composite ceramic coatings show totally different characteristics both in morphology and tribological properties, in detail: the surface of the SCS+HA coating is composed of micro-platy structure, but the surface of the SCS+T coating is composed of nano-crystal particles. Compared with SCS+HA coating, the wear resistance of SCS+T coating is better under higher load (5N). The HA coating deposited by biomimetic method has lower friction coefficient and better wear resistance compared with the composite coatings. The result of this paper is valuable for the research on the preparation of biocompatibility controllable composite ceramic coatings with good tribological properties. (3) The preparation and characteristics researches of patterned TiO₂ bioceramic film on Titanium alloy. Using bioactive and patterned design methods of Titanium alloy stent implants, micro-nano patterned TiO₂ bioceramic films have been prepared on Titanium alloy substrates via the acid/alkali pretreatment combining sol-gel method and the templating sol-gel method. The influence of experimental parameters upon the morphology of the target films has been studied by using AFM. The wettability and tribological properties of the target films have been studied. The results indicate: the feature of the patterned films can be controlled by changing certain experimental parameters. The tribological results indicate: comparing with TiO₂ film made by tradition sol-gel method, the wear resistance of the patterned film is better which proves a certain kind of patterned structure can improve the wear resistance of the film. This work expands the patterned TiO₂ bioceramic films'application and provides the theoretical basis for the development of new wearable artificial joints.