原位在线监测多因素协同对玻璃纤维/环氧树脂复合材料热老化性能的影响

针对玻璃纤维增强聚合物(GFRP)复合材料作为火电烟囱内衬的服役老化问题，以玻璃纤维/环氧树脂(GF/EP)复合材料为研究对象，用正交试验法研究温度、偶联剂含量和热流老化时间等因素对GF/EP复合材料热损伤后的质量损失率、弯曲强度和剪切性能的影响。采用金相显微图像处理法测量计算GF/EP复合材料的孔隙率，使用自主设计并搭建的原位在线监测系统对GF/EP复合材料进行测试。结果表明，不同因素对GF/EP复合材料性能的影响程度不同。偶联剂含量的增加会有限改善GF/EP复合材料的质量损失率，而温度因素对复合材料弯曲强度的影响较大，复合材料本身存在的后固化行为会影响弯曲性能的变化趋势，随温度升高弯曲强度总体下降了11.8%。GF/EP复合材料的层间剪切强度与热老化时间密切相关，16 h相比8 h热流老化后的层间剪切强度均值提高了10.2%。 

Effects of multiple factors on thermal aging properties of glass fiber/epoxy composites using in-situ monitoring

In order to investigate the aging problem of glass fiber reinforced polymer(GFRP) composites as the lining of thermal power chimney, the glass fiber/epoxy(GF/EP) composite was taken as the research object. The effects of temperature, coupling agent content and heat flux aging time on the mass loss rate, bending strength and shear properties of GF/EP composite were studied by orthogonal test. The porosity of the GF/EP composite was measured and calculated by means of metallographic microscopic image processing and in-situ real-time detection system. The results show that different factors have different effects on the properties of GF/EP composites. The increase of coupling agent content can improve the mass loss rate of GF/EP composite. Temperature has a great influence on the bending strength. The post-curing behavior of the GF/EP composite itself will affect the change trend of bending performance, which still decreases by 11.8% as the temperature increasing. The interlaminar shear strength of the GF/EP composite is closely related to the thermal aging time, and the mean interlaminar shear strength is 10.2% higher at 16 h than that at 8 h.