On the Lightweight Potential of Laser Additive Manufactured NiTi Triply Periodic Minimal Sheet Lattices

The lattice structure of NiTi alloy has long been of interest in the smart device fields due to its lightweight structure and flexible design. Recently, with the advancement of additive manufacturing technology, shell lattice structures based on triply periodic minimal surfaces (TPMS) have emerged as promising candidates for load‐bearing and energy absorption applications. However, for the commonly used laser additive manufacturing technology, the microstructure of NiTi is highly sensitive to its processing thermal history. This phenomenon is particularly prominent in micro‐laser powder bed fusion, where the printed feature size can be less than 100 μm, and the coupling between structure and material becomes more obvious. This is a potential problem that could hinder the further lightweighting of NiTi lattice structures. This study is the first to investigate the evolution of surface morphology, deformation recovery, compression behavior, and energy absorption performance of TPMS sheet lattice structures of NiTi with a large range of wall thickness from 65 to 500 μm, and relative density (RD) from 5% to 40%. These findings provide important insights into the design of lightweight TPMS lattices for 3D‐printed smart systems, where controlling shape memory recovery, energy dissipation, and structural adaptability is crucial for future lightweight (RD ≤ 10%) design.