fig2

Figure 2. (A) In-plane deformations of kirigami metamaterials during the initial phase, as shown in the force-displacement curve. This stage is characterized by buckling bifurcations and the transition from 2D to 3D microstructures^[30]; (B) In-plane deformations of thicker kirigami metamaterials, where the structural thickness is ten times the beam width to prevent out-of-plane buckling, satisfying the plane strain condition^[31-33].