Metallic lattice structures via additive manufacturing: Applications, challenges and opportunities in aerospace and defence

Abstract

Lattice structures: periodic, porous architectures formed from repeating unit cells are rapidly transforming the landscape of lightweight engineering, particularly in aerospace and defence sectors. These structures offer superior strength-to-weight ratios, enhanced energy absorption, and improved thermal management compared to monolithic materials. Traditional manufacturing methods are limited in their ability to fabricate such complex geometries; however, additive manufacturing (AM), especially metal-based techniques like Laser Powder Bed Fusion (LPBF) and Electron Beam Melting (EBM), has enabled the precise realization of intricate lattice topologies. This comprehensive review categorizes metallic lattice structures into strut-based, surface-based (e.g., TPMS), shell-based, and hybrid designs, and evaluates their mechanical behaviour, thermal properties, and application relevance. Key metallic materials including titanium alloys, aluminum alloys, nickel-based superalloys, and steels are discussed with respect to printability, structural performance, and suitability for aerospace and defence applications. The review further surveys real-world implementations such as Airbus lattice partitions, lattice-cored turbine blades, underbelly blast shields, and lattice-enhanced warhead liners. Emphasis is placed on design methodologies, including analytical modeling, finite element simulation, topology optimization, and AI driven generative design, which are increasingly integrated with AM constraints. Additionally, the paper addresses practical manufacturing considerations like support structures, build orientation, in-situ monitoring, and post-processing. Through structured evaluation and literature synthesis, this work provides critical insights into the design, fabrication, and deployment of metallic lattices for high-performance engineering applications.