Geometrical Accuracy Analysis of Ti-6Al-4V Trusses Manufactured by Electron Beam Melting Process

Abstract

Lattice structures made of metal materials are very interesting since their structural efficiency is elevated, thanks to their good mechanical properties and light weight. Additive manufacturing processes are appropriate to produce those structures. However, the peculiar geometry of lattice structures causes the manufacturing process to create rather significant unconformities, affecting the structures’ mechanical properties. In this article, small trusses with different diameters were produced through electron beam melting (EBM) by varying the process parameters, like the orientation and the position in the build chamber. Then, their diameter was evaluated and compared with the nominal one. It was found that the orientation in the chamber was very influential on the geometrical error, as well as the nominal diameter, while the position in the building chamber was uninfluential. In particular, the highest deviation was found for the specimens oriented at 0° and those with a diameter of 1 mm. Moreover, a similar result was detected for the ovalisation of the truss section too.