Characterization and mechanism of accelerated curing of adhesives by in situ ultrasonic vibration for bonded joints
Characterization and mechanism of accelerated curing of adhesives by in situ ultrasonic vibration for bonded joints
复制标题
原位超声波振动加速胶粘剂固化的表征及机理
DOI：
10.1515/polyeng-2019-0217
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发表时间：
2020-01-01
影响因子：
2
通讯作者：
Chen, Yizhe
中科院分区：
文献类型：
--
作者：
Wang, Hui;Yuan, Yao;Chen, Yizhe
超声振动可以加速环氧树脂的固化。以前的研究还没有探讨超声的非热效应。在本文中，我们展示了使用原位超声振动消除热效应的加速固化过程。阐明了非热效应的加速机制。采用双酚A环氧树脂/低分子量聚酰胺650体系作为接头的胶粘剂，以碳纤维增强塑料（CFRP）/铝合金接头为粘接对象。超声振动通过超声工具头施加到接头中的CFRP层合板上。采用傅里叶变换红外光谱和差示扫描量热法对胶粘剂的常规固化和超声固化过程进行了表征。结果表明，该胶粘剂的固化速度可提高2500%。通过对Kamal模型的改进，提出了一种能较好地描述超声固化过程的新模型。该模型表明，超声可以降低活化能。温度监测证实，脉冲超声可以在固化过程中保持粘合剂的温度稳定。动态热机械分析表明，脉冲超声加速了固化过程，提高了胶粘剂的力学性能。超声波促进了树脂和固化剂之间的传质，增加了反应物之间的碰撞几率，从而提高了反应速率。
Ultrasonic vibration can accelerate the curing of epoxy compounds. Previous studies have not explored the nonthermal effects of ultrasound. In this article, we show the accelerated curing process using in situ ultrasonic vibration that removes the thermal effect. The acceleration mechanism of nonthermal effects is clarified. Bisphenol A epoxy resin/low molecular weight polyamide 650 system was used as the adhesive of the joint, and carbon-fiber-reinforced plastic (CFRP)/aluminum alloy joint was used as the bonding object. Ultrasonic vibration was applied in situ to the CFRP laminate in the joint through an ultrasonic tool head. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to characterize the process of conventional curing and ultrasonic curing of adhesives. Results show that the curing rate of the adhesive can be increased by 2500%. By improving the Kamal model, we describe a new model that can describe the ultrasonic curing process very well. The model shows that ultrasound can reduce the activation energy. Temperature monitoring confirmed that pulsed ultrasound can maintain the temperature of the adhesive stable during the curing process. Dynamic thermomechanical analysis showed that pulsed ultrasound accelerates the curing process and improves the mechanical properties of the adhesive. Ultrasound promotes mass transfer between the resin and the curing agent and increases the collision probability between the reactants, thus increasing the reaction rate.