Research On The Shaping Process Of Femoral Artery Vascular Tissue Based On Piezoelectric Micro-jet

It is one of the most common methods to treat cardiovascular diseases that artificial blood vessels replace diseased vessels.Meanwhile,materials and forming process of artificial blood vessels have an effect on treatment to a great degree.Nowadays,with the wide application of 3D bio-printing technology in the medical field,personalized artificial blood vessels are of great significance for precision medical treatment.This paper aims to design a 3D printing vascular tissue platform with multi-functional forming process based on piezoelectric micro-jet,and verifying the reliability of the printing platform through experimental research.The main contents of this paper are as follows:Firstly,this article takes the femoral artery as the research object,selects the abdominal cavity CT image of the volunteer as the data source,carries on the threshold analysis and the blood vessel separation,and establishes the three-dimensional model of the femoral artery by 3D reconstruction software named Mimics,which provide some foundation for printing models and mechanics analysis.Then according to different external diameter(10mm,8mm)and wall thickness(1mm,0.8mm)of blood vessels,four straight-tube vascular models are constructed,which are named respectively as "width-thin","width-thick","narrow-thin" and "narrow-thick".And the force situation of four vascular models are simulated with the finite element static mechanical analysis.The results show that the "width-thick" vascular model with the outer diameter of 10mm and the thickness of 1mm has excellent comprehensive performance.Secondly,in order to achieve the preparation of artificial blood vessels,a 3D printing platform is built with double forming process that are cross-linking and powder bonding forming.A mechanical frame,motion system,forming cavity,piezoelectric jet and other modules are built with the modular design concept.At the same time,the control system is designed for the 3D printing platform,including Trio-based hardware parts and software parts based on the Motion Perfect 3.3 platform.Finally,the dot matrix experiment is used to study the jetting accuracy through the constructed 3D printing platform.The results show that the jetting dot diameter can be up to 100?m and distribution diameter is in the range of 100-500?m,and the influence of nozzle clogging on the droplet ejection is discussed.In addition,the effects of printing parameters(spray distance,piezoelectric micro-nozzle driving voltage and moving speed)on the forming quality of printed parts are analyzed based on the designed cross-linking forming experiment.Then based on the optimal parameters,3%sodium alginate solution and 5%calcium chloride solution are used as materials to manufacture artificial blood vessels,which are subjected to mechanical tests and compared with the results of finite element analysis.The results show that the printed artificial blood vessels meet the mechanical requirements.The above research can provide theoretical and experimental basis for stent-free printing of artificial blood vessels,and it can be used as reference for printing personalized artificial tissue.