非均匀薄膜在刚性曲面上滑动粘附的强韧化机理研究

The adhesion mechanics of bio-inspired adhesive films recently has become a hot topic for researchers in the mechanic community. The interfacial frictional sliding and the heterogeneity of the film as two strengthening and toughening factors for adhesion of thin films have also attracted some scholars’ attention. However, the sliding adhesion of a heterogeneous film on a curved surface, which is a practically more important but also more challenging problem, has not been studied yet. Motivated by such a gap, this proposal aims to establish a new adhesion model, explore the effects of frictional sliding, surface waviness and the heterogeneity of the film on the adhesion behavior of the film, and try to clarify the coupling mechanism among these strengthening and toughening factors. In the new model, the finite deformation beam theory and hyperelastic constitutive relations will be adopted, reasonable interfacial frictional law and peeling criterion will be utilized, and the equilibrium equation and boundary conditions will be derived by using the principle of virtual work. On this basis, theoretical analysis based on the membrane theory and numerical calculations based on the finite element method will be conducted in order to predict the adhesion behavior of the film. The implementation of this proposal should provide theoretical guide for the design and optimization of biomimetic adhesive materials.

近年来仿生粘附薄膜的粘附力学成为力学工作者研究的热点，界面滑动摩擦和薄膜非均匀设计这两种粘附强韧化机制也引起一些学者的重视，然而非均匀薄膜在刚性曲面上滑动粘附这一有很强应用价值也更具挑战性的科学问题还没有得到足够的关注。本项目拟针对这一问题建立新的粘附力学模型，研究滑动摩擦、表面起伏以及薄膜的非均匀性等因素对薄膜粘附力学行为的影响规律，探讨这几种不同强韧化机制之间的耦合作用机理。我们将采用有限变形梁理论和超弹性本构关系，选择合适的界面摩擦律和脱粘判据，根据虚功原理导出粘附系统的平衡方程和边界条件。在此基础上，通过基于膜理论的理论分析和基于有限元方法的数值分析给出薄膜的粘附力学规律。本项目的研究成果可为仿生粘附材料的设计和优化提供理论指导。

近年来仿生粘附薄膜的粘附力学成为力学工作者研究的热点。本项目对超弹性薄膜（或宽梁）在曲面上的滑动粘附问题进行了深入研究。首先基于连续介质力学原理和计及厚度方向应变的运动学假设，为超弹性薄膜建立了考虑其大应变和弯曲效应的理论模型；基于该模型，分析了超弹性薄膜在刚性平面上的粘附力学行为；进一步，对超弹性薄膜在曲面上滑动粘附行为进行了深入研究。研究表明：大应变对软薄膜的稳态剥离力影响显著，而弯曲刚度影响初始剥离阶段的粘附行为。在滑动粘附情形，滑动摩擦能够显著增强薄膜的粘附韧性和粘附强度。所取得的研究成果为进一步探讨超弹性薄膜在非均匀性曲面上粘附规律提供了很好的研究基础，也可为仿生粘附材料的设计和优化提供帮助。