Fabricating polymer/HEA-hybrid topological lattice structure for enhanced mechanical properties

作者：Zhang, Wentao; Yao, Zhongzheng; Zhang, Sihan; Liu, Sinan; Ying, Huiqiang; Ge, Jiacheng; Fu, Shu; Lou, Yu; Li, Xiang; Wu, Zhenduo; Zhu, He^*; Chen, Shuangqin^*; Lan, Si^*

来源：Progress in Natural Science-Materials International, 2022, 32(6): 800-805.

DOI：10.1016/j.pnsc.2022.12.005

• TISIN/AG MULTILAYER COATINGS
• HIGH-ENTROPY ALLOY
• SIZE
• DEFORMATION
• ULTRALIGHT
• STRENGTH

Metamaterials such as architected lattice structures have aroused broad interest in being applied as mechanical supports for their lightweight and custom-shaped capabilities. Although various prior efforts have been devoted, a multiscale fabrication of micro-nano lattice structures without penalizing the mechanical properties is still a challenging but highly desirable task. Here we put forward a strategy to produce a mechanically enhanced micro-nano lattice structure by conformally depositing a CoCrFeNiTi high-entropy alloy (HEA) coating layer onto a three-dimensional (3D) printed polymer skeleton. The template for the 3D printing employs a six-membered tricapped trigonal prism (6M-TTP) structure derived from a medium-range order structure motif in amorphous alloys. The topological complexity of the 6M-TTP can substantially avoid the stress concentration by offering stress-release channels, while the HEA film incorporating with amorphous and nanocrystalline constituents can further reinforce the lattice architecture through its size hardening effect. Benefitting from the above, the fabricated polymer/HEA-hybrid lattice exhibits a high specific compressive strength (similar to 0.055 MPa kg(-1) m(3) at a density below 500 kg m(-3)), a superior elastic recoverability (similar to 70% recovery rate under >30% compression), an enhanced plasticity (40% strain) and a high specific modulus (0.135 MPa kg(-1) m(3)). Our strategy initiates a perspective way to fabricate multiscale micro-nano lattice structures with improved mechanical properties, which could be extended to widespread metamaterial research.

• 单位
  南京理工大学