基于材料性能时变特性的复合材料固化过程多场耦合数值模拟

针对热固性树脂基复合材料固化过程中各种复杂的物理化学变化之间的相互影响,建立了基于材料性能时变特性的复合材料固化过程的二维多场耦合计算模型。该模型由已知的3个经典复合材料固化过程子模型构成,包括热-化学模型、树脂黏度模型和树脂流动模型。在此基础上,将固化过程中材料性能的时变特性引入多场耦合计算模型中。通过与文献中实验结果的比较,证明了所建立的模型具有较高的可靠性。对AS4/3501-6复合材料层合平板的固化过程进行了数值模拟,重点研究了固化过程中纤维体积分数变化及材料参数的时变特性对固化过程中温度、固化度和树脂压力等参量的影响。分析结果表明:考虑纤维体积分数变化和材料性能的时变特性后,固化过程中复合材料层合板中心温度峰值明显减小,树脂压力随时间的变化将有所滞后。

Multi-field coupled numerical simulation for curing process of composites with time-dependent properties of materials

According to the interrelationship of the complex physical and chemical processes during the curing process of thermoset resin composites, a multi-field coupled two-dimensional model based on the time-dependent properties of materials during the curing process of composites was established. The model incorporated three typical existing sub models for curing process of composites: thermo-chemical model, resin viscosity model and resin flow model. On the basis, the time-dependent properties of material performances during the curing process were introduced into multi-field coupled calculation model. According to the comparison with experiment data in reference, the model established was proved to possess relative superior reliability. The curing process of AS4/3501-6 composite laminates were numerical simulated. The effects of the variation of fiber volume fraction and time-dependent properties of material performances on the temperature, the degree of cure, the pressure of resin and other parameters during curing process was studied attentively. The results show that when taking the changes of fiber volume fraction and time-dependent properties of material parameters into consideration, the peak value of temperature at the center of composite laminate decreases significantly, and the change of resin pressure verses time lags.