Bottom-up optimization of additive manufacturing: Process–structure–property relationships in laser powder bed fusion

In additive manufacturing (AM), especially Laser (Powder Bed Fusion (L-PBF), having excellent and consistent mechanical properties is important for high-value applications in aerospace, automobile industries, and biomedical engineering. This study employs a novel, complementary bottom-up approach to systematically investigate how scanning strategies (spiral, island, and bi-directional) and part orientations influence the microstructural and mechanical properties of L-PBF components. Microstructural characterization, using optical microscopy, scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD), allowed the evaluation of grain size, porosity, and crystallographic texture. Mechanical properties and their relationship with the microstructural features of tensile strength, yield strength, elastic modulus, strain percentage, and hardness were evaluated. Ultimately, the results demonstrate that both scanning strategies and part orientations have a considerable effect on the mechanical properties of key features such as strength, ductility, and anisotropy. Specifically, island scanning showed the best ductility while spiral scanning demonstrated better strength at the cost of greater brittleness. Additionally, this study demonstrated that controlling scanning strategies and part orientation offers valuable insights for optimizing the L-PBF process, with significant implications for the design and fabrication of high-performance components in demanding industrial applications.