Quantifying Mechanical Property Degradation of Cellular Material Using As-Fabricated Voxel Modeling for the Material Extrusion Process

When fabricating cellular material using the material extrusion process, manufacturing errors arise due to approximation of geometries during slicing and tool-path generation, as well as the finite filament size. Moreover, since a cellular material generally consists of a large number of structural elements such as struts and plates, it has large bounding surfaces to be approximated during the AM process, which can increase manufacturing error. The errors degrade the mechanical properties of a fabricated cellular material. In this paper, an as-fabricated voxel modeling approach is proposed to quantify mechanical property degradation. An additively manufactured strut is modeled using voxels based on material extrusion and its effective structural characteristics such as a cross-sectional area and the second moment of area are evaluated. The property degradation is assessed by comparing mechanical properties from tensile tests and performing discrete homogenization with obtained structural characteristics.