Improved Failure‐Resistance of Lattices Through Two Dual‐Phase Design Strategies and Three Polycrystalline‐Like Mechanisms

Polycrystal structures offer promising avenues to design lattices for improved performances. Two truss units with distinct strengths are used, respectively, as matrix phase (MP) and reinforced phase (RP) to construct the architected dual‐phase polycrystal‐like lattices (DPL). Six DPLs are designed under the RP “hindering” or “strengthening” strategy, and fabricated by micro additive manufacturing method. Quasistatic compression is carried out to obtain the compressive responses, as well as finite element method to reveal the stress evolution over these lattices. Specifically, the existence of the dual phase leads to the high‐stress deformation bands in the form of passing MP with bypassing RP. Besides, the RP “strengthening” strategy is more effective compared to “hindering” strategy in improving energy‐absorbing capacity. In addition, the improved failure‐resistance of DPL mainly originates from the three polycrystal‐like deformation mechanisms including “phase squeeze”, “phase boundary slip”, and “phase rotation”, which are effective in delaying lattices’ global damage.