Influence of the Unit Cell Geometrical Parameter to the Mechanical Properties of Ti6Al4V Open-Porous Scaffolds Manufactured by Selective Laser Melting

Abstract

Selective laser melting (SLM) are getting more and more established as reliable methods for producing open-porous scaffolds with accurately controlled pore size, strut size, and porosity. However, the optimal geometrical parameter of the unit cell by SLM remained unclear. In this study, we evaluated the effect of unit geometrical parameters to the mechanical properties of porous scaffolds by finite element analysis method and Mechanical testing method. Six rhombic dodecahedron unit cells were designed with different geometrical parameter and the scaffolds manufactured by SLM using Ti6Al4V. The compression testing results show that the specimens with the same pore size, the elastic modulus and the strength are increased with increasing strut size and the specimens with the same strut size, the elastic modulus and the strength are decreased with increasing strut size. The porosity can be calculated by pore size and strut size. The compression strength of the porous scaffolds is 114MPa~258MPa and the quasi-elastic gradient is 3.18Gpa~8.64Gpa, which are similar to human bone. The simulation values are different from the experiment values but the variation tendency is in accordance.