With emphasis on the Face-Centered Rhombic Dodecahedron (FRD) topology, this thesis examines the mechanical behavior and structural performance of triply periodic minimal surface (TPMS) lattice structures made using Laser Powder Bed Fusion (L-PBF). For comparison, the uniform and functionally graded variations (FRD-30, FRD-40, and FRD-45) were evaluated against Gyroid and Fischer–Koch–S structures. They were developed with a constant average volume percentage of 45%. The relationship between relative density and the mechanical performance of these designed materials was further validated by Ashby-Gibson modeling. The evaluation of internal porosity, defect morphology, and geometric integrity was done using high-resolution X-ray computed tomography (XCT). According to the results, the graded FRD-30 structure had the most uniform defect distribution and the lowest pore volume, but the geometric complexity of the FRD-40 structure resulted in higher porosity variability.