Design of biomimetic fibrillar interfaces: 2. Mechanics of enhanced adhesion
Design of biomimetic fibrillar interfaces: 2. Mechanics of enhanced adhesion
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DOI：
10.1098/rsif.2004.0005
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发表时间：
2004-11-22
影响因子：
3.9
通讯作者：
Jagota, A
中科院分区：
文献类型：
--
作者：
Hui, CY;Glassmaker, NJ;Jagota, A
这项研究讨论了通用纤维结构的强度和韧性。我们表明，将原纤维拉出与基材的粘合接触所需的应力 sigma(c) 的形式为 sigma(c) = sigma(0)Phi(chi)。在该方程中，sigma(0) 是界面强度，Phi(chi) 是满足 0 1 的无量纲函数，但对于 chi < 1 对缺陷不敏感。重要参数 X 还控制均匀变形的非纤维（平坦）界面的稳定性。利用这些结果，我们表明，纤维表面单位面积的失效功可能比相同材料的平坦界面的固有粘附功高得多。此外，我们还发现，原纤维的横截面尺寸控制着拉力，拉力随着原纤维半径的减小而增加。最后，原纤维长度的增加被证明会增加分离原纤维界面所需的工作。除了涉及单个原纤维的计算之外，我们还研究了包含许多原纤维的完美界面的等负载分配（ELS）的概念。我们获得了在均等负载分配下理想化原纤化界面的实际粘附功。然后，我们分析纤维表面从刚性基材上的剥离情况，并建立 ELS 的标准。
This study addresses the strength and toughness of generic fibrillar structures. We show that the stress sigma(c) required to pull a fibril out of adhesive contact with a substrate has the form sigma(c) = sigma(0)Phi(chi). In this equation, sigma(0) is the interfacial strength, Phi(chi) is a dimensionless function satisfying 0 1, but is flaw insensitive for chi < 1. The important parameter X also controls the stability of a homogeneously deformed non-fibrillar (flat) interface. Using these results, we show that the work to fail a unit area of fibrillar surface can be much higher than the intrinsic work of adhesion for a flat interface of the same material. In addition, we show that cross-sectional fibril dimensions control the pull-off force, which increases with decreasing fibril radius. Finally, an increase in fibril length is shown to increase the work necessary to separate a fibrillar interface.Besides our calculations involving a single fibril, we study the concept of equal load sharing (ELS) for a perfect interface containing many fibrils. We obtain the practical work of adhesion for an idealized fibrillated interface under equal load sharing. We then analyse the peeling of a fibrillar surface from a rigid substrate and establish a criterion for ELS.