Zhang Kai, Duan Huiling, Karihaloo Bhushan L, Wang Jianxiang
State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871, China.
Proc Natl Acad Sci U S A. 2010 May 25;107(21):9502-6. doi: 10.1073/pnas.0912066107. Epub 2010 May 3.
We reveal the sophisticated and hierarchical structure of honeybee combs and measure the elastic properties of fresh and old natural honeycombs at different scales by optical microscope, environmental scanning electron microscope, nano/microindentation, and by tension and shear tests. We demonstrate that the comb walls are continuously strengthened and stiffened without becoming fragile by the addition of thin wax layers reinforced by recycled silk cocoons reminiscent of modern fiber-reinforced composite laminates. This is done to increase its margin of safety against collapse due to a temperature increase. Artificial engineering honeycombs mimic only the macroscopic geometry of natural honeycombs, but have yet to achieve the microstructural sophistication of their natural counterparts. The natural honeycombs serve as a prototype of truly biomimetic cellular materials with hitherto unattainable improvement in stiffness, strength, toughness, and thermal stability.
我们揭示了蜜蜂蜂巢复杂的分层结构，并通过光学显微镜、环境扫描电子显微镜、纳米/微压痕以及拉伸和剪切试验，在不同尺度下测量新鲜和陈旧天然蜂巢的弹性特性。我们证明，通过添加由回收蚕茧加固的薄蜡层，蜂巢壁不断得到强化和硬化，而不会变得易碎，这让人联想到现代纤维增强复合材料层压板。这样做是为了提高其在温度升高时抗坍塌的安全裕度。人工工程蜂巢仅模仿天然蜂巢的宏观几何形状，但尚未达到其天然对应物的微观结构复杂性。天然蜂巢作为真正仿生细胞材料的原型，在刚度、强度、韧性和热稳定性方面有着迄今难以企及的改进。
