基于超声在线监测的民机复合材料固化行为研究

发布时间：2018-03-25 06:40

  本文选题：复合材料维修　切入点：固化　出处：《中国民用航空飞行学院》2015年硕士论文

【摘要】：深入研究复合材料维修固化反应过程,运用超声技术实时在线监控固化进程,分析不同固化参数对固化后材料性能的影响,对于开发更优的维修固化工艺,实现固化过程的可控具有重要意义。 本文采用riedman (FR), Flynn-Wall-Ozawa (FRO), Kissinger-Akahira-Sunose (KAS)三种非模型法计算并绘制了WHUT-Esys208环氧树脂体系的固化速率和活化能与固化度的关系曲线,分析了环氧树脂体系的固化反应阶段和固化行为。研究表明,固化反应逐渐从自催化反应机理转变为n阶反应机理,这与模型拟合法研究的结果基本吻合。三种非模型拟合法都能较好地表征该体系的固化行为,其中KAS法的结果最能准确地反映该体系的固化行为,FWO法的结果略有偏差,FR法仅趋势与另两种一致。 研究运用超声波在线监测方法监测WHUT-Esys108室温固化环氧树脂系统的固化过程。研究表明,随着固化的进行,超声波的振幅值和能量值均不断发生变化。将其绘制成曲线后能在一定程度上反映树脂体系的固化过程。通过公式计算出在固化过程中的超声衰减并绘图,可以明显区分出固化反应的不同阶段,实现超声波幅值变化与固化反应进程表征的结合。 研究固化保温温度和固化升温速率对固化后复合材料力学性能的影响,并结合光学显微镜研究固化参数与微观形貌之间的关系。研究表明,该树脂体系存在最佳固化温度：在保温时间60min,升温速率2℃/min下,实验得到的最佳温度为120℃；不同升温速率对复合材料的拉伸性能有一定影响,总体上呈现为升温速率越慢固化后复合材料的力学性能越好,但具体原因尚待确定。
[Abstract]:The curing process of composite materials is studied in depth. The ultrasonic technology is used to monitor the curing process in real time and on-line. The effect of different curing parameters on the properties of the cured materials is analyzed in order to develop a better curing process. It is of great significance to realize the controllable curing process. In this paper, the curing rate, activation energy and curing degree of WHUT-Esys208 epoxy resin system are calculated and plotted by using three kinds of non-model methods: riedman FRX, Flynn-Wall-Ozawa FRON and Kissinger-Akahira-Sunose Kass. The curing reaction stage and curing behavior of WHUT-Esys208 epoxy resin system are analyzed. The curing reaction gradually changed from the self-catalytic reaction mechanism to the n-order reaction mechanism, which is basically consistent with the results of the model fitting method. All three kinds of non-model fitting methods can better characterize the curing behavior of the system. The results of KAS method can best reflect the curing behavior of the system. The results of FWO method are slightly deviated from the results of FWO method and the trend of FR method is only consistent with that of the other two methods. In this paper, the ultrasonic on-line monitoring method is used to monitor the curing process of WHUT-Esys108 epoxy resin system at room temperature. The amplitude value and energy value of ultrasonic wave change continuously. The curve can reflect the curing process of resin system to a certain extent. The ultrasonic attenuation during the curing process is calculated and plotted by formula. The different stages of curing reaction can be distinguished obviously, and the combination of ultrasonic wave amplitude change and the characterization of curing reaction process can be realized. The effects of curing temperature and heating rate on the mechanical properties of the composites were studied. The relationship between the curing parameters and the microstructure of the composites was studied by means of optical microscope. The optimum curing temperature of the resin system is 120 鈩，

本文编号：1661983