Electron beam melting of Ti-6Al-4V lattice structures: correlation between post heat treatment and mechanical properties

Abstract

Additive manufacturing processes are considered advanced manufacturing methods. It would be possible to produce complex shape components from a computer-aided design model in a layer-by-layer manner. As one of the complex geometries, lattice structures could attract lots of attention for both medical and industrial applications. In these structures, besides cell size and cell type, the microstructure of lattice structures can play a key role in these structures’ mechanical performance. On the other hand, heat treatment has a significant influence on the mechanical properties of the material. Therefore, in this work, the effect of the heat treatments on the microstructure and mechanical behaviour of Ti-6Al-4V lattice structures manufactured by electron beam melting was analysed. The main mechanical properties were compared with the Ashby and Gibson model. It is very interesting to notice that a more homogeneous failure mode was found for the heat-treated samples. The structures’ relative density was the main factor influencing the mechanical performance of the heat-treated samples. It is also found that the heat treatments were able to preserve the stiffness and the compressive strength of the lattice structures. Besides, an increment of both the elongation at failure and the absorbed energy was obtained after the heat treatments. Microstructure analysis of the heat-treated samples confirms the increment of ductility of the heat-treated samples with respect to the as-built one.

A feasibility study to improve the processability of pure copper produced via laser powder bed fusion process

“…One of the key advantages of the AM processes is freedom in design that brings the complexity for free in the part design and production. Therefore, the production of complex shape parts, including the lattice structures or internal channels, was facilitated using metal AM processes [8,9]. A heat exchanger made of copper and copper alloys is one of these complex components that can be the first candidate to be produced via metal AM technologies [10].…”