NiTi alloy lattice structures are crucial for reusable energy absorption due to their shape memory effects. However, existing NiTi alloy lattice structures always suffer from localized deformation bands during loading, causing local strains to exceed the recoverable strain limit of the alloy and significantly reducing their reusable energy-absorbing capacity. In this study, we developed a NiTi alloy helical lattice structure (HLS) to effectively prevent localized deformation bands. This is attributed to its struts distributing stress and strain uniformly through torsional deformation, thereby alleviating local stress concentrations and suppressing the formation of localized deformation bands. Additionally, its unit cells provide mutual support and reinforcement during deformation, effectively preventing the progression of localized deformation bands. The NiTi alloy HLS exhibits superior reusable energy absorption compared to previously reported reusable energy-absorbing materials/structures and enhanced damage tolerance under large compression strain. This study provides valuable insights for the development of high-performance reusable NiTi alloy energy-absorbing lattice structures.

中文翻译：

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NiTi 合金螺旋晶格结构，具有高可重用能量吸收和增强的损伤容限


由于其形状记忆效应，NiTi 合金晶格结构对于可重复使用的能量吸收至关重要。然而，现有的 NiTi 合金晶格结构在加载过程中总是受到局部变形带的影响，导致局部应变超过合金的可恢复应变极限，并显着降低其可重复使用的能量吸收能力。在这项研究中，我们开发了一种 NiTi 合金螺旋晶格结构 （HLS），以有效防止局部变形带。这归因于其支柱通过扭转变形均匀分布应力和应变，从而减轻了局部应力集中并抑制了局部变形带的形成。此外，其单元在变形过程中提供相互支撑和加固，有效防止局部变形带的发展。与以前报道的可重复使用的能量吸收材料/结构相比，NiTi 合金 HLS 表现出卓越的可重复使用能量吸收能力，并且在大压缩应变下具有更强的损伤容限。本研究为高性能可重复使用的 NiTi 合金吸能晶格结构的开发提供了有价值的见解。