Characterization Of Pore Structure And Numerical Simulation Of Compressive Behavir Of Porous Titanium With Helical Pores

With its outstanding mechanical compatibility and biocompatibility, the poroustitanium sintered by titanium wire has great potential for practical application inbone repairing. However, the failure mechanism of the pore structure of the poroustitanium sintered by titanium wire is not very clear, which limits its furtherapplication. Therefore, the pore structure of the porous titanium was characterized atfirst, and then the compressive mechanical behavior of porous titanium wasresearched by the use of numerical simulation. The results are as follows:The porous titanium prepared is regularly arranged by lots of typical cells witha certain structure. By giving the expressions of porosity of porous titanium and itslimiting conditions, the analysis shows that the porosity of the porous titaniumdepends mainly on the diameter of titanium wire, pitch diameter, pitch, layerspacing and adjacent spacing of the spirochete. Decreasing the diameter of titaniumwire and pitch diameter of the spirochete or increasing the pitch, layer spacing andadjacent spacing of the spirochete will all contribute to increase the porosity ofporous titanium. In particular, the porosity of the porous titanium with typical cellincreases with the decrease of the diameter of the titanium wire or the increase ofedge length of cell and the layer spacing of the spirochete.The compressive mechanical properties of the porous titanium mainly dependon the porosity and the relative size of the sintering neck. The compressivemechanical properties of porous titanium cell decreases with the increase of porosity.Specifically, the compressive yield strength and Young’s modulus of porous titaniumcell increase with the increase the diameter of titanium wire or the decrease of theside length of cell. The expressions for the influence of the porosity on thecompressive yield strength and Young’s modulus of porous titanium have beengotten by analyzing the above results.Stress concentration occurs at the sintering neck firstly when the poroustitanium is under the compressive loading. The relative diameter of the sinteringneck has a huge impact on the compressive mechanical properties of porous titaniumcell, while the influence of the relative length of the sintering neck is smaller.Among three sintering neck, the sintering neck near the double free end is the mostimportant contributory factor. With the increase of the relative diameter of thesintering neck, the compressive yield strength and Young’s modulus of poroustitanium cell will also be significantly increased. The expressions for the influenceof the sintering neck on the compressive yield strength and Young’s modulus ofporous titanium have also been obtained. The expressions of the compressive yield strength and Young’s modulus ofporous titanium have finally been given in this paper.