On the Effects of Process Optimization for Ti-6Al-2Sn-4Zr-2Mo Lattice Structures Produced by Electron Beam Powder Bed Fusion

A lattice structure is a topologically ordered repetition of an elementary cell within a predefined volume. These specific structures ensure high mechanical performances with reduced material use. Despite, their complexity, the production of such designs is made possible thanks to additive manufacturing (AM) processes. In particular, the electron beam powder bed fusion (PBF-EB) process allows the easy production of such complex structures with high-performance metallic materials such as Ti-6Al-2Sn-4Zr-2Mo (Ti6242). This work presents the optimization of EB-PBF process for producing Ti6242 lattice structure and analyzes the effect of process tuning on the lattice structure morphometry. Non-destructive X-ray computed tomography analyses are used to disclose the causal relationship between the beam current, focus offset, and scan speed and the produced lattice structure. The results showed that the process parameters greatly influenced the lattice morphology. The measured relative density and the strut size values were systematically larger than the nominal design.