湿热环境对T800碳纤维/环氧树脂基复合材料力学性能的影响

Effect of hygrothermal environment on mechanical properties of T800 carbon fiber/epoxy resin composites

对T800碳纤维/环氧树脂基复合材料进行湿热老化实验,通过质量变化、老化前后表面形貌、红外光谱、动态力学性能,层间剪切和压缩实验,研究3.5%(质量分数,下同)NaCl溶液和去离子水两种介质分别在70℃下溶液浸泡对碳纤维/环氧树脂基复合材料力学性能的影响。结果表明:T800碳纤维/环氧树脂基复合材料在去离子水和3.5%NaCl溶液中的吸湿率相对较低,分别为0.82%和0.67%;未老化试样纤维与基体之间黏结良好,在3.5%NaCl溶液老化后纤维与基体界面破坏相比去离子水中老化更严重;经去离子水中浸泡后剪切强度降低8.8%,压缩强度降低4.3%;在3.5%NaCl中浸泡后剪切强度降低10.1%,压缩强度降低4.7%。在两种溶液老化后试样的T g降低,但相差不大。此次研究结果对T800碳纤维/环氧树脂基复合材料在腐蚀环境中的应用提供了依据。

The hygrothermal aging test of T800 carbon fiber/epoxy resin composites was carried out.Through mass change,surface morphology before and after aging,dynamic mechanical properties,infrared spectroscopy,interlayer shear and compression tests,the effects of solution immersion in deionized water and 3.5%(mass fraction,the same as below)NaCl solution at 70℃on the mechanical properties of carbon fiber/epoxy resin composites were studied.The results show that the moisture absorption rate of T800 carbon fiber/epoxy resin matrix composite is relatively low in deionized water and 3.5%NaCl solution,which is 0.82%and 0.67%,respectively;Good adhesion between unaging sample fiber and matrix,after aging in 3.5%NaCl solution,the interface damage between fiber and matrix is more serious than that in deionized water.After immersion in deionized water,the shear strength is decreased by 8.8%,the compressive strength is decreased by 4.3%.After soaking in 3.5%NaCl,the shear strength is decrease by 10.1%,the compressive strength is decreased by 4.7%.The T g of the samples decreased after aging in the two solutions,but the difference is not significant,at the same time,no new substances are generated or chemical reactions occur.The research results provide a basis for the application of T800 carbon fiber/epoxy resin composites in corrosive environment.