Wagih Ahmed, Mahmoud Hassan A, Tao Ran, Lubineau Gilles
Mechanical Engineering Program, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Mechanics of Composites for Energy and Mobility Lab, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Polymers (Basel). 2023 Jan 4;15(2):259. doi: 10.3390/polym15020259.
This paper presents a strategy towards achieving thermoplastic adhesive tapes with high toughness by microstructuring conventional tapes using tailored defects. Toughened tape was manufactured using two layers of a conventional tape where the bondline between the two adhesive layers was microstructured by embedding tailored defects with specific size and gap between them using PTFE film. Mode I toughness of the toughened tape was characterized experimentally. A high-fidelity finite element model was implemented to describe the toughening mechanisms using double cantilever beam simulations and end notch flexural tests. The model considers for the plasticity of the adhesive layer, the decohesion at the adherend-adhesive and adhesive-adhesive interfaces and progressive damage inside the adhesive layer. The adhesive-adhesive interface with the tailored defects inside the adhesive layer enables crack migration between adherend-adhesive interfaces, crack propagation at adhesive-adhesive interface, backward crack propagation under the defect, and plastic deformation of the adhesive ligament. The maximum toughness improvement of the tape with tailored defects of equal width and gap between two successive defects of 2 mm reached 278% and 147% for mode I and II, respectively, compared to conventional tape.
本文提出了一种策略，即通过使用定制缺陷对传统胶带进行微结构化处理，来实现具有高韧性的热塑性胶带。增韧胶带是由两层传统胶带制成的，其中两层胶粘剂层之间的粘结线通过使用聚四氟乙烯薄膜嵌入具有特定尺寸和间隙的定制缺陷进行微结构化处理。通过实验对增韧胶带的I型韧性进行了表征。利用双悬臂梁模拟和端部切口弯曲试验，建立了一个高保真有限元模型来描述增韧机理。该模型考虑了胶粘剂层的塑性、被粘物-胶粘剂和胶粘剂-胶粘剂界面处的脱粘以及胶粘剂层内部的渐进损伤。胶粘剂层内部具有定制缺陷的胶粘剂-胶粘剂界面能够使裂纹在被粘物-胶粘剂界面之间迁移、在胶粘剂-胶粘剂界面处扩展、在缺陷下方反向扩展以及胶粘剂韧带发生塑性变形。与传统胶带相比，具有等宽度定制缺陷且相邻两个缺陷之间间隙为2mm的胶带，其I型和II型韧性的最大提高分别达到278%和147%。
