Microstructure and Mechanical Performance of Ti–6Al–4V Lattice Structures Manufactured via Electron Beam Melting (EBM): A Review

Abstract

Electron beam melting (EBM) process is an additive manufacturing process largely used to produce complex metallic components made of high-performance materials for aerospace and medical applications. Especially, lattice structures made by Ti-6Al-4V have represented a hot topic for the industrial sectors because of having a great potential to combine lower weights and higher performances that can also be tailored by subsequent heat treatments. However, the little knowledge about the mechanical behaviour of the lattice structures is limiting their applications. The present work aims to provide a comprehensive review of the studies on the mechanical behaviour of the lattice structures made of Ti-6Al-4V. The main steps to produce an EBM part were considered as guidelines to review the literature on the lattice performance: (1) design, (2) process and (3) post-heat treatment. Thereafter, the correlation between the geometrical features of the lattice structure and their mechanical behaviour is discussed. In addition, the correlation among the mechanical performance of the lattice structures and the process precision, surface roughness and working temperature are also reviewed. An investigation on the studies about the properties of heat-treated lattice structure is also conducted.

A Comprehensive Overview on the Latest Progress in the Additive Manufacturing of Metal Matrix Composites: Potential, Challenges, and Feasible Solutions

“…Studies have compared the powder recyclability in EBM and LPBF and found that they are rather similar [69][70][71]. In contrast to LPBF, a vacuum atmosphere (around 1 × 10 -5 mbar) is applied in the EBM chamber, which is useful to avoid any contamination, especially for the processing of reactive materials such as titanium alloys or gamma titanium aluminide intermetallics [72]. Moreover, since EBM employs a different source of energies, compared to the one used in LPBF, higher scanning rates and generally preheating of the powder (even up to 1100 °C) is possible.…”

WAAM process for metal block structure parts based on mixed heat input

“…Flexible design technique: The outstanding feature of the AM process is that it applies the layer by layer manufacturing method, which can create almost any complex geometry [17]. The layer by layer deposition strategy is in contrast to subtraction due to its limitation in design flexibility such as the need for fixtures, different tooling, possible collisions in the manufacture of complex geometry, and the difficulty of tool access to more profound and invisible areas [24].…”

Microstructure and Mechanical Properties of AISI 316L Produced by Directed Energy Deposition-Based Additive Manufacturing: A Review

“…In powder bed systems, a layer of powder is spread on the building platform or on the previously solidified layer and is selectively fused via an energy source that can be either electron beam or laser beam [6][7][8]. The ability to produce high-resolution features and internal channels, as well as precision dimensional control, are considered the main advantages of powder bed AM processes [5,9,10]. In contrast, in powder/wire feed systems, the material is fed directly inside a melt pool which is already formed by a focalized heat source on the substrate or on the already deposited layer.…”