中文摘要：

采用超声波透射法成功实现了实时在线监测环氧树脂在不同条件下的固化反应过程,研究了超声波振幅衰减随固化反应时间的变化关系,探讨了中温条件下模具厚度和玻璃纤维对环氧树脂固化反应过程的影响。结果表明：振幅衰减呈现出先增加后减小并趋于稳定的规律;随着固化反应的进行,振幅衰减能够准确地反映出环氧树脂体系出现凝胶点的时间和黏稠态—凝胶态—玻璃态各相态的变化过程。提高温度能缩短固化时间,增加厚度和玻璃纤维能在一定程度上延缓凝胶点出现的时间,并对其机理进行了讨论。超声波在线监测为环氧树脂基复合材料的加工成型和制作工艺提供了理论依据和重要的技术手段。

英文摘要：

Ultrasonic transmission technique is successfully employed to real-time online monitor curing process of epoxy resin under different conditions. The relationship between ultrasonic amplitude attenuation and curing time of epoxy resin as well as the effect of mould thickness and glass fiber on the curing reaction process of epoxy resin under medium temperature are investigated, respectively. Experimental results indicate that ultrasonic attenuation firstly increases then decreases and finally tends to be stable. As the curing reaction proceeds, the appeared time of gel point and the phase change process transformed from viscous-gel state to gel-glass state can be accurately meas- ured by ultrasonic attenuation. It is shown that the curing time can be shorten by raising temperature, the appeared time of gel point can be delayed by adding thickness and glass fiber in some degree and their mechanisms are dis- cussed. The ultrasonic online monitoring can provide a theoretical basis and important technical support for the molding and processing technology of epoxy resin composite materials.