Programmable multifunctional auxetic metamaterials via concave rib architecture

Auxetic metamaterials exhibit counterintuitive deformation (lateral expansion under tension) with significant potential in aerospace and automotive applications. However, conventional designs are limited by fixed negative Poisson’s ratios (NPR), single deformation modes, and restricted load responses. We introduce a concave-rib-modified auxetic metamaterial (CRMAM) that overcomes these limitations. This architecture enables programmable Poisson’s ratio (spanning negative to positive values), multi-step deformation, and sequential load plateaus, enhancing specific energy absorption ( SEA ) by over 135% compared to traditional re-entrant structures. CRMAMs also exhibit velocity-dependent dynamic crushing,…

• NN
  National Natural Science Foundation of China
• CP
  China Postdoctoral Science Foundation