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| Abstract: |
| In order to characterize the mechanical behaviors of the Velcro and Dual-lock fasteners, a series of tests including the butt-joint (BJ) monotonic tensile and shear, mixed tensile-shear with various loading angles, the loading rates effects, the double cantilever beam (DCB) fracture and 180° peel experiments were performed. The tensile and shear tests results showed that the mechanical behaviors of Velcro fastener separation are analogous to ductile materials, and those of Dual-lock fasteners are more like brittle ones. The mixed tensile-shear with various loading angles tests results demonstrated that magnitudes of the peak stresses in 30°, 45°, and 60° have no significant differences, which are lower than those in the monotonic tensile or shear tests for the two fasteners. The effects of the loading rate tests show that the peak stresses of the Velcro fastener manifested good performance at the loading rate of 10 to 20 mm/min in the tensile and shear conditions, and the Dual-lock did it well around the loading rates of 10 to 20 mm/min in the tensile condition. The cohesive zone model (CZM) is employed to numerical predict the DCB fracture and the 180° peel tests. The CZM predictions results are proven to commendably capture the two tests separation processes, of the tow fasteners, and the numerical results agreed well with the peeling tests data of the Dual lock fasteners. The results and discussions in this study are expected to bring more understanding to engineers and designers about the performance of Velcro and Dual lock fasteners. |
| Key words: Velcro fastener Dual-lock fastener mechanical behaviors cohesive zone model numerical prediction |
| DOI：10.11916/j.issn.1005-9113.17127 |
| Clc Number:TQ432.2;TQ433.439 |
| Document Code::A |
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| Descriptions in Chinese: |
| Velcro® 和 Dual-lock 粘扣力学性能的实验与数值分析 张军，王佳琦，袁振伟 （郑州大学 化工与能源学院，郑州 450001） 创新点说明：Velcro® 和 Dual-lock 粘扣虽然被广泛应用，但其力学性能却研究很少，本文通过拉伸，剪切，从不同拉伸和剪切角度的影响、不同拉伸和剪切速率的影响实验，以及双臂梁和180o剥离实验，分别研究两种粘扣的力学性能，并分析比较它们各自特点。然后采用内聚力模型，分析了双臂梁和180o剥离断裂过程。计算结果与实验结果相符合，尤其是模拟Dual-lock 粘扣180o剥离过程，能很好地分析波动开裂过程。 研究方法： 实验采用Instron力学试验机，并利用Arcan夹具。选用3M生产的两种不同性能的粘扣，基板采用工字型铝材并用特殊固定方式。分别对两种粘扣进行了拉伸，剪切，不同拉伸和剪切角度影响，不同拉伸和剪切速率的影响实验，以及双臂梁和180o剥离实验。用ABAQUS软件，利用内聚力粘接单元，对双臂梁和180o剥离断裂过程进行了模拟。 研究结果： 拉伸和剪切实验发现Velcro®粘扣的力学性能与延展性材料类似，Dual-lock粘扣更像脆性材料；不同的施加力角度对其粘接强度影响不明显；施加力速率对其粘接强度有一定影响，Velcro®和Dual-lock粘扣在10-20 mm/min拉伸速率时有很高的粘接强度。利用内聚力粘接单元，对双臂梁断裂和180o剥离过程进行了模拟，计算结果与实验结果符合，尤其是模拟Dual-lock 粘扣180o剥离过程，能很好地分析波动开裂过程。 结论： Velcro®粘扣应用在延展性链接处适合，Dual-lock 粘扣适合脆性链接；这两种粘扣采用10-20 mm/min的拉开速度有较高的粘接强度。内聚力模型能很好模拟这两种粘扣的断裂过程，可作为理论工具对粘扣进行设计和研发。 关键词：Velcro®粘扣，Dual-lock粘扣，力学性能，内聚力模型，数值预测 |
