Tensile tests were assessed to evaluate the ageing effects on carbon fiber/epoxy resin laminates exposed to ozone and water immersion. Laminates with distinct fiber arrangements (unidirectional - UD and plain weave - PW) were tested under transversal and longitudinal tensile strength at room (22°C) and high (88°C) temperatures after conditioning. The transversal tensile strength tests of UD laminates performed at room temperature show that the water immersion decreased this property in 28% when compared to non-conditioned samples. Ozone atmosphere also deteriorates the tensile strength considerably, drop of 27%. It was expected a higher drop in water immersion conditioning than in ozone atmosphere due to this conditioning attacks preferentially the external surface of specimen contrariwise the water immersion has diffusion inside the epoxy matrix. Tensile strength at high temperature shows more accentuated degradation for UD specimens exposed to water immersion (50% drop) than ozone (25%). Higher temperatures favor the degradation of the polymeric matrix and fibers/matrix interface. Tensile strength of PW laminates non-conditioned and conditioned with ozone, tested at room temperature, presented tensile strength results slightly different, 17% lower. When submitted to water immersion the results have dropped 26%, which are similar to unidirectional composite. At high temperature, PW laminate attacked with ozone had tensile strength reduced in 7%, while after water immersion the drop achieved 18%. These results show that water immersion affected the composite much more than ozone. Fractographic analyses confirmed that the combination between high temperature and conditioning promoted the degradation of matrix and fiber/matrix interface.

中文翻译：

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臭氧和水浸泡后老化对碳/环氧树脂 F8552 层压板室温和高温拉伸强度的影响

对拉伸试验进行了评估，以评估暴露于臭氧和水浸泡的碳纤维/环氧树脂层压板的老化效应。在调节后在室温 (22°C) 和高温 (88°C) 下测试横向和纵向拉伸强度下具有不同纤维排列（单向 - UD 和平纹 - PW）的层压板。在室温下进行的 UD 层压板的横向拉伸强度测试表明，与未调节的样品相比，水浸使该性能降低了 28%。臭氧气氛也大大降低了抗拉强度，下降了 27%。由于这种调节优先攻击试样的外表面，相反，水浸在环氧树脂基体内部具有扩散，因此预计水浸调节的下降幅度高于臭氧气氛。与臭氧 (25%) 相比，暴露于水浸 (50%) 的 UD 样品在高温下的拉伸强度显示出更严重的退化。较高的温度有利于聚合物基质和纤维/基质界面的降解。PW 层压板的拉伸强度未经调节和用臭氧调节，在室温下测试，其拉伸强度结果略有不同，低 17%。当进行水浸时，结果下降了 26%，与单向复合材料相似。在高温下，经臭氧攻击的 PW 层压板的拉伸强度下降了 7%，而浸水后下降了 18%。这些结果表明，与臭氧相比，浸水对复合材料的影响更大。