Hydrothermal aging mechanisms and service life prediction of twisted bamboo fiber wound composites

Twisted bamboo fiber (TBF) wound composites produced using filament winding exhibit excellent poten-tial for applications in lightweight and high-strength rotary structural components. Hydrothermal aging crucially influences the durability of TBF-wound composites. The effects of hydrothermal aging on the microstructure, hygroscopic properties, and mechanical properties of TBF Naval Ordnance Laboratory (TBF-NOL) composites were examined in this study to elucidate the hydrothermal aging mechanisms of TBF-NOL composites and predict their service life. The moisture absorption behavior of the TBF-NOL composites conformed to Fick's second law. After a 30 d water immersion test at 70 degrees C, the TBF-NOL com-posites exhibited a high moisture content, leading to a significant decrease in the tensile, bending, and shear properties. Hydrothermal aging significantly deteriorated the TBF/epoxy resin interface in the TBF-NOL composites. The effect of temperature on the hydrothermal aging of the TBF-NOL composites was more pronounced than that of humidity. This study predicts that the bending properties of TBF-NOL composites could be maintained at the 40-50% level for 5-10 years, depending on the degree of exposure to hydrothermal environments. The service-life prediction results can guide the practical appli-cation of TBF-wound composites.(c) 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Twisted bamboo fiber (TBF) wound composites produced through filament winding have great potential for lightweight and high-strength rotary structural components. This study examines the effects of hydrothermal aging on the microstructure, hygroscopic properties, and mechanical properties of TBF-NOL composites and predicts their service life. The results show that hydrothermal aging significantly affects the TBF/epoxy resin interface and temperature has a greater impact than humidity. The bending properties of TBF-NOL composites can be maintained at 40-50% for 5-10 years depending on the degree of exposure to hydrothermal environments. This research provides guidance for practical applications of TBF-wound composites.