Experimental and Numerical Investigation of Mechanical Properties of Different Lattice Structures Manufactured from Medical Titanium Alloy by Using Laser Beam-Powder Bed Fusion

Abstract

This study focused on the manufacturing of different lattice structures from Ti-6Al-4V ELI alloy with the laser beam-powder bed fusion (LB-PBF) method, which is expected to have potential applications in aviation and especially the medical field. The mechanical properties of these structures were investigated experimentally and numerically. The porous lattice systems, manufactured according to the optimum laser process parameters, with the repetitive periodic structure were designed in five different topologies (BCC, BCCZ, FCC, FCCZ and DIAMOND) and three different porosities (60, 75, 90%). The mechanical properties and damage mechanisms of the lattice structures were obtained by static compression tests. BCC and DIAMOND systems showed similar characteristics in terms of stress-compression elongation compared to other lattice systems, with the rods having the same orientation. It was observed that XYZ modification of BCC lattice system was more effective than the modification of FCC system in terms of rigidity and strength. The damage mechanism and stiffness values suggested that the DIAMOND lattice system could be a model that can be used in porous implant designs owing to its homogeneous deformation behavior and mechanical properties similar to trabecular bone. Numerical models were created where numerical results and static experiments converge considerably well. The numerical and experimental results were quite similar, and the maximum difference was below 7.7%. © 2021, ASM International.