论文标题
鱼皮的较高损伤耐受性
Superior damage tolerance of fish skins
论文作者
论文摘要
皮肤是许多动物中最大的器官。它针对敌对环境和捕食攻击的保护功能使高机械强度成为至关重要的特征。在这里，我们测量了低音鱼皮的机械性能，发现鱼皮是高度延展的，破裂应变高达30-40％，破裂强度为10-15 MPa。鱼皮表现出应变的行为。拉伸可以有效地消除预先存在的孔和边缘缺口附近的应力浓度，这表明皮肤具有高度损伤的耐受性。我们的测量确定了几毫米的缺陷长度，超过了大多数工程材料的缺陷。鱼皮的应变膨胀和损伤耐受性通过基于代理的胶原蛋白网络模型来解释，在该模型中，从纳米纤维中组装的承重胶原蛋白微纤维在拉伸时会进行伸直和重新定位。我们的研究启发了薄，柔软但高度抗性且广泛适用于软机器人的人造皮肤的发展。
Skin is the largest organ of many animals. Its protective function against hostile environments and predatorial attack makes high mechanical strength a vital characteristic. Here, we measured the mechanical properties of bass fish skins and found that fish skins are highly ductile with a rupture strain of up to 30-40% and a rupture strength of 10-15 MPa. The fish skins exhibit a strain-stiffening behavior. Stretching can effectively eliminate the stress concentrations near the pre-existing holes and edge notches, suggesting that the skins are highly damage tolerant. Our measurement determined a flaw-insensitivity length of several millimeters, which exceeds that of most engineering materials. The strain-stiffening and damage tolerance of fish skins are explained by an agent-based model of collagen network in which the load-bearing collagen microfibers assembled from nanofibrils undergo straightening and reorientation upon stretching. Our study inspires development of artificial skins that are thin, flexible, but highly fracture-resistant and widely applicable in soft robots.
