Triply periodic minimal surfaces (TPMS) metamaterials and shape-memory polymer (SMP) art materials are known for their beneficial attributes in novel scientific and industrial fields. Through TPMS designs, low weight accompanied by high surface area are achievable, which are known as crucial parameters in many fields, such as tissue engineering. Moreover, SMPs are well-suited to generate force or to recover their permanent shape by means of an external stimulus. Combining these properties is possible by fabricating TPMS-based metamaterials made out of SMPs, which can be applicable in numerous applications. By considering different level volume fraction of four types of TPMS-based lattices (diamond, gyroid, IWP, and primitive), we focus on the effect of micro-architecture on shape-memory characteristics (i.e., shape recovery, shape fixity, and force recovery) as well as mechanical properties (elastic modulus and Poisson's ratio) of these art metamaterialshth官网首页. For this purpose, shape-memory effect (SME) is simulated employing thermo-visco-hyperelastic constitutive equations coupled with the time-temperature superposition principle. It is observed that by increasing the level volume fraction of each lattice type, the elastic modulus, shape fixity, and force recovery increase, while the shape recovery diminishes. Such behaviors can be attributed to different deformation modes (flexural or uniaxial) in SMP TPMS-based metamaterials. Furthermore, it is shown that the Poisson's ratio has a nonlinear behavior in these structures. The art metamaterials introduced in this study have the advantage of providing the possibility of designing implants, especially in bone defects tailored with different micro-architectures depending on each patient's specific need.

　　中文翻译：

　　三周期最小表面 (TPMS) 超材料和形状记忆聚合物 (SMP) 智能材料以其在新的科学和工业领域的有益属而闻名。通过 TPMS 设计，可以实现低重量和高表面积，这在组织工程等许多领域被称为关键参数。此外，SMP 非常适合通过外部产生力或恢复其永久形状。通过制造由 SMP 制成的基于 TPMS 的超材料，可以结合这些特，这些超材料可应用于多种应用。通过考虑四种基于 TPMS 的晶格（菱形、螺旋形、IWP 和原始）的不同水平体积分数，我们关注微架构对形状记忆特（即形状恢复、形状固定、和力恢复）以及这些智能超材料的机械能（弹模量和泊松比）。为此，形状记忆效应 (SME) 采用热粘超弹本构方程和时间-温度叠加原理进行模拟。可以观察到，通过增加每种晶格类型的水平体积分数，弹模量、形状固定和力恢复增加，而形状恢复减少。这种行为可以归因于不同的 可以观察到，通过增加每种晶格类型的水平体积分数，弹模量、形状固定和力恢复增加，而形状恢复减少。这种行为可以归因于不同的 可以观察到，通过增加每种晶格类型的水平体积分数，弹模量、形状固定和力恢复增加，而形状恢复减少。这种行为可以归因于不同的基于 SMP TPMS 的超材料中的变形模式（弯曲或单轴）。此外，表明泊松比在这些结构中具有非线行为。本研究中引入的智能超材料具有提供设计植入物的可能的优势，特别是在根据每个患者的具体需要采用不同微结构定制的骨缺损中。