提出了一种适用于85℃“中温环境”监测环氧树脂固化过程的Lamb波实时监测系统,在85℃“中温环境”下选用兼有A₀模式和S₀模式的Lamb波监测了钢槽中不同厚度环氧树脂的固化过程,研究了超声Lamb波声衰减系数随环氧树脂固化时间的变化规律。结果表明,固化过程中环氧树脂A₀模式Lamb波声衰减系数一致性差、不稳定;S₀模式Lamb波声衰减系数一致性好且稳定,呈现先小幅度下降后急速上升,然后逐渐下降并趋于平稳的变化趋势,能够准确反应环氧树脂初始黏流态、凝胶态和玻璃态等不同固化状态。基于超声Lamb波固化过程在线监测方法为树脂基复合材料成型工艺的设计和优化提供了基础数据和技术支撑。

In this paper, a Lamb wave real-time monitoring system for monitoring curing process of epoxy resin at the medium temperature of 85℃ is proposed. The curing process of epoxy resin with different thickness in steel tank was monitored by both A₀ mode and S₀ mode of Lamb waves at the medium temperature of 85℃ and the change law of the attenuation coefficient of Lamb waves with curing time of epoxy resin was studied. The results show that acoustic attenuation coefficient of A₀ mode inepoxy resin in the curingprocess has poor consistency and instability, while acoustic attenuation coefficient of S₀ mode has good consistency and stability, which first decreases slightly, then increases rapidly, and then gradually decreases and tends to be stable. It can accurately characterize different curing stages of epoxy resin including the initial viscous flow, gel and glass stages. This study provides basic data and technical support for the design and optimization of resin matrix composite molding process based on Lamb wave on-line monitoring method.