不同热氧环境对T800碳纤维/环氧树脂复合材料力学性能的影响EI北大核心CSCD

不同热氧环境(70,130,190℃)对碳纤维复合材料的性能有着重要的影响。分析了不同热氧环境下T800碳纤维/环氧树脂复合材料的失重特性,并对比了老化前后的表面形貌、红外光谱、动态力学性能和层间剪切性能。结果表明:在热氧老化初始阶段,质损率急速上升,老化温度越高质量损失越快;试样表面形貌随热氧温度的升高其破坏程度逐渐加剧,在190℃老化后,纤维表面树脂脱落严重,纤维与纤维之间出现裂缝空隙,无树脂填充,在此老化温度下,试样发生了不可逆化学变化;试样的玻璃化转变温度会随老化温度的升高而变大,但内耗呈现先降低后增大再降低的趋势,在70,130,190℃热氧老化后试样剪切强度分别提高6.0%,13.7%和2.1%。相关实验结果和实验现象可为后续研究新型国产T800碳纤维/环氧复合材料提供数据参考。

Effects of different thermal-oxidative environments on mechanical properties of T800 carbon fiber/epoxy resin composites

Different thermal-oxidative environments (70, 130 ℃ and 190 ℃) have important effects on the properties of carbon fiber composites. The mass loss characteristics of T800 carbon fiber/epoxy resin composites under different thermal-oxidative environments were analyzed, and the surface morphology, infrared spectra, dynamic mechanical properties and interlaminar shear properties of T800 carbon fiber/epoxy resin composites before and after aging were compared. The results show that in the initial stage of thermal-oxidative aging, the mass loss rate is increased rapidly, and the higher the aging temperature, the faster the mass loss. The extent of damage sample surface morphology is gradually increased with the increasing of thermal-oxidative temperature, after aging at 190 ℃, the resin on the fiber surface falls off seriously, the cracks and gaps appear between the fibers, and there is no resin filling, at this aging temperature, the sample has an irreversible chemical change. The glass transition temperature of the sample is increased with the increase of aging temperature, but the internal friction is decreased at first, then increased and then decreased. After thermal-oxidative aging at 70, 130 ℃ and 190 ℃, the shear strength of the samples is increased by 6.0%, 13.7% and 2.1%, respectively. The relevant test results and phenomena can provide data reference for the follow-up study of the new domestic T800 carbon fiber/epoxy composites.