Effect of hydrothermal aging on the mechanical properties of nanocomposite pipes

Abstract

Abstract The aim of this study is to minimize the decrease in the mechanical properties of materials exposed to environmental conditions by adding nano additives, thereby increasing service life. It has been reported in the literature that boron nitride nanoparticles (BNNP), a multi-walled carbon nanotube (MWCNT), and hybrid (MWCNT + BNNP) nano additives improve the mechanical properties of FRPs and increase their lifetime. For this reason, in this study, filament wound BNNP, MWCNT, and MWCNT + BNNP hybrid reinforced carbon fiber epoxy composite pipes (CFRPs) were produced with (± 55°)4 configurations and 8 layers. Then, composite pipes were exposed to the hydrothermal aging process in distilled water at 80 °C for 7, 14, and 21 days in order to examine the effects of hot water absorption behavior on mechanical properties such as hardness, and density. The hardness and density measurements were realized in accordance with ASTM standards. The hardness, and density properties of water exposed BNNP, MWCNT, and MWCNT + BNNP hybrid reinforced and non-reinforced CFRPs were examined and compared with unexposed specimens according to ASTM standards. As a result of this study, it was observed that the hardness and density values of the specimens exposed to aging reinforced with nano-sized material were even higher than the hardness and density values of the neat epoxy unexposed to aging. Consequently, although water absorption caused a loss in the mechanical properties of the material, the negative effects of water absorption were minimized thanks to the added nano additives.