Tuning the Properties of Additively Manufactured Tungsten Ultra-fine Lattices by Adjusting Laser Energy Density and Lattice Geometry

Additive manufacturing (AM) offers unique advantages for manufacturing complex geometries from refractory metals, which are difficult to form using traditional processes. In this study, tungsten lattices of approximately 5 × 5 × 5 mm were additively manufactured using various laser energy densities and lattice topologies. Applications for these lattice structures include catalysts for monopropellant and green propulsion, wicking materials in heat pipes, and high thermal load structures. The use of AM allows these lattices to be integrated into other structures, with the capability of tuning properties such as mechanical properties, pressure drop, and surface area. This work investigates the effects of lattice topology and print parameters on the mechanical and fluid flow properties of these lattices. Due to the small unit cell and strut size of these lattices, the print parameters directly impact the lattice feature resolution, which were characterized using scanning electron microscopy. Compression tests were performed to determine the effect of laser energy density on lattice strength. Flow tests were performed with water and nitrogen to characterize the pressure drop across these samples as a function of printing laser energy density and lattice topology. Our paper will discuss the results of these experiments and their implications.