Boundary integrity-based Gyroid minimal surface NiTi porous structure achieved through non-proportionally scaled deformation method with superior mechanical property

Triply periodic minimal surface structures (TPMS) have garnered significant attention owing to their exceptional mechanical properties, biomimetic curvature attributes, and favorable printability characteristics. Nonetheless, existing design methodologies for porous structures exhibit certain limitations. In particular, the Boolean operation method can result in damaged boundary cells within intricate models. This research introduces a nonproportionally scaled deformation model approach for generating the Gyroid Square Become Circle (GSBC) structure with an integrated boundary. Following fabrication through selective laser melting of NiTi, morphological assessments conducted via scanning electron microscopy and 3D reconstructions affirmed its printability. The compression behavior of GSBC was investigated through finite element simulations and compression testing, comparing to traditional Gyroid Boolean Intersection Operation (GBIO) structures. The findings revealed that GSBC exhibited superior compression performance and enhanced energy absorption capacity. A comprehensive analysis was carried out, encompassing porosity, CT reconstruction outcomes, inclination angles, curvature distribution characteristics, and failure mechanisms. The examination of inclination angles demonstrated a discernible correlation between the inclination angle and stress distribution under uniaxial compression loading conditions. This study is poised to offer valuable insights into the design and utilization of TPMS-based models for complex structures, along with the integration of mechanical properties in porous structures.