The Manufacture And Finite Element Analysis Of Bileaflet Artificial Heart Valve

A artificial heart valve is a man-made appliance which is made of mechanical stuff or biological tissue to replace the natural valve, which can not be restored to a normal function.As yet, the bileaflet mechanicial heart valve is the forth generation of the mechanical heart valve,and is applied widespread well in clinic experiments because of central fluency and permanent durability. This paper focused on the manufacture processing technology of the bileaflet mechanicial heart valve which was designed by institute of biomaterials and surface engineering of Southwest Jiaotong University.The research work of this thesis started with the concept of "artificial heart valve " ,and then introduced process of heart valve in our bodies, foreign and domestic development, present situation and the requirement of its function. Titanium alloy becomes preferred material of mechanical heart valve because of fine synthetical function, but it is the typical material which is processed difficultly,and it's hard to satisfy the technical requirement if we use the traditional methods. Based on eletro discharge theory in this paper, technics of ring about electrical discharge machining ( EDM) and low speed wire electrical discharge machining (LS-WEDM) has been researched. It's intended to develop technology of the ring of titanium alloy. Design and manufacture of technological furnishment was studied, selection and making of electrode was dicussed,and parameter of machining was optimized.Finally ,after ring was electrical machined,ring was annealed in order to reduce to deformation of ring ,and eleminate remains stress. The process of showpiece testified that the technics of ring in the paper was workable.Then, technics of leaflet which is made from pyrolitic carbonhas been researched, including designing and manufacture of technologic fumishment and choice of electrical parameter.Lastly, based on the ANAYS software of finite element analysis methods, A computational method for simulating assembling process of the heart mechanical valve is presented in this paper. The maxium value of extrusion distortion was computed in the assemble process, and washer material was optimized by using the ANAYS software.