Comparing Mechanical and Geometrical Properties of Lattice Structure Fabricated Using Electron Beam Melting

To design lattice structure, a uniform voxel based approach is widely used which divides a part into unit volumes (e.g., cubes) and maps lattice topology into those volumes. In contrast, conformal lattice structures represent a second design method for constructing lattices in which unit cells are constructed parallel to the surface to be reinforced and are deformed in a manner that enables them to conform to the surface. In this paper, the strength of lattice structures designed using these two methods (uniform voxel based and conformal) are compared based on additive manufacturing (AM) process effects. For this purpose, spheres filled with three types of lattice structure are fabricated using electron beam melting technology and tested in compression. Effects of AM processes are studied in two ways – volumetric and structural performance equivalence. Struts in lattice structures are observed through a microscope to examine volume-equivalence and tests are simulated numerically and compared to identify structural equivalence.