论文标题
2D晶格材料的意外弯曲行为
Unexpected bending behavior of 2D lattice materials
论文作者
论文摘要
由于泊松比的可调节迹象，架构的2D格子材料吸引了形状变动应用。人们普遍认为，当材料沿一个方向弯曲时，阳性和负泊松比分别导致抗塑料和触发曲线。在这里，以恒星形晶胞为示例，以2D光束晶格为例，我们在理论上表明并在实验上证明这并不总是正确的。以固定的泊松比，我们发现由梁的横截面纵横比控制的抗塑料和触发弯曲曲率之间的过渡。横梁的扭转与弯曲之间的竞争中，这种出乎意料的行为根源，可以通过哥塞拉特连续模型很好地捕获。
Architected 2D lattice materials are appealing for shape-shifting applications due to the tunable sign of Poisson's ratio. It is commonly believed that the positive and negative Poisson's ratios lead to anticlastic and synclastic curvatures respectively when the material is bent in one direction. Here, taking 2D beam lattices with star-shaped unit cells as examples, we show theoretically and demonstrate experimentally that this is not always true. At a fixed Poisson's ratio, we find a transition between anticlastic and synclastic bending curvatures controlled by the beam's cross-sectional aspect ratio. Such an unexpected behavior roots in the competition between torsion and bending of the beams, and can be well captured by a Cosserat continuum model.
