Graded triple periodic minimal surface (TPMS) structures fabricated by selective laser melting (SLM) are superior candidates for lightweight and energy-absorbing applications. Previous studies have reported that TPMS structures with a constant wall thickness showed excellent performance; however, exploring the properties of TPMS structures with a graded thickness remains a challenge because of the lack of design theory. This study proposes a novel method for the design of graded-thickness TPMS structures. The manufacturability, mechanical properties and energy absorption capacities of Ti6Al4V graded samples are summarised and compared for different thicknesses and TPMS types. The findings reveal that manufacturing accuracy is influenced by the designed thickness and overhang angle. The constant-thickness TPMS samples exhibited good stiffness, strength and energy absorption capacities, while the graded-thickness samples avoided large stress fluctuations and showed higher elastic moduli and cumulative energy absorption values than the constant-thickness samples. The local curvature distribution also predicted the deformation behaviour of the TPMS structures. This graded-thickness modelling method offers a new perspective on porous structure design, and the experimental results indicate the importance of selecting the proper unit type and graded parameters for most applications.

通过选择性激光熔化 (SLM) 制造的渐变三周期最小表面 (TPMS) 结构是轻质和能量吸收应用的绝佳候选者。先前的研究报告称，具有恒定壁厚的 TPMS 结构表现出优异的性能；然而，由于缺乏设计理论，探索具有渐变厚度的 TPMS 结构的特性仍然是一个挑战。本研究提出了一种设计渐变厚度 TPMS 结构的新方法。总结并比较了不同厚度和 TPMS 类型的 Ti6Al4V 梯度样品的可制造性、机械性能和能量吸收能力。研究结果表明，制造精度受设计厚度和悬垂角度的影响。等厚 TPMS 样品表现出良好的刚度，强度和能量吸收能力，而梯度厚度样品避免了大的应力波动，并显示出比恒定厚度样品更高的弹性模量和累积能量吸收值。局部曲率分布还预测了 TPMS 结构的变形行为。这种分级厚度建模方法为多孔结构设计提供了新的视角，实验结果表明为大多数应用选择合适的单元类型和分级参数的重要性。