在超材料结构粘合剂的膝盖剪切的不对称硬化
Chenghai Li1, Qiang Guo1, Robert Chambers2
1Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093, USA. s3cai@ucsd.edu.
Soft matter
|August 12, 2024
概括
具有厚厚的支结构的超材料结构粘合剂 (MSAs) 显示了增强的粘合力. 不同的薄膜厚度和光束角度为先进的应用解锁不对称和可切换的附着性能.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 机器人技术 机器人技术 机器人技术
背景情况:
- 超材料结构粘合剂 (MSAs) 根据结构设计提供可调节的粘合性能.
- 厚厚的支结构对MSA粘附的影响尚不清楚.
- 现有的研究缺乏对支结构几何如何影响粘附性能的全面分析.
研究的目的:
- 为了研究厚厚的支结构对MSA的粘附性质的影响.
- 探索不同的终端薄膜厚度和光束倾斜角度如何影响粘附强度和能量.
- 了解这些新型粘合系统中控制粘合行为的潜在机制.
主要方法:
- 用薄粘合层和不对称的厚梁结构制造的MSA,其结尾用不同厚度的薄膜.
- 在不同终端薄膜厚度 (t) 和光束倾斜角度 (θ) 的MSA上进行了拉皮剪切试验.
- 实验结果与理论预测的比较,基于裂捕获机制和裂开始地点的分析.
主要成果:
- 带有厚度终结膜 (t = 2 mm) 的MSA表现出两倍的有效粘附能量,而不会影响剪切强度.
- 与固体样本相比,含有薄膜终端 (t = 0.5 mm) 的MSA显示显著增强剪切强度 (~2.8x) 和粘附能 (~18.6x),由于新的裂纹开始,与理论背道而.
- 粘附强度不对称系数 (τ2/τ1) 在厚薄膜上达到约2.2,粘附能量不对称系数 (Γ1/Γ2) 通过调整光束倾斜角度 (θ) 在薄膜上达到约5.3.
结论:
- 厚厚的支结构可以显著提高MSA的粘附性能,其性能取决于薄膜厚度和束形状.
- 该研究揭示了裂捕获和启动的机制,这对于优化MSA设计至关重要.
- 结果为开发先进的MSA提供了洞察力,用于机器人,可穿戴设备和具有挑战性的环境,如粗的表面或水下条件.
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