Mechanical behavior of glass fiber‐reinforced hollow glass particles filled epoxy composites under moisture environment

Abstract The utilization of hollow glass particle‐filled fiber‐reinforced composites in marine applications necessitates a proper understanding of their behavior when exposed to moisture environments. In this study, the glass fiber‐reinforced composites reinforced with 0%–30% volume fraction of glass microspheres were fabricated and immersed in seawater and distilled water conditions for monotonic tensile and flexural testing. The degradation mechanisms were analyzed by dynamic mechanical analysis (DMA), Fourier transform infrared spectroscopy (FT‐IR), and scanning electron microscopy (SEM). Moisture absorption results showed an increasing trend with the inclusion of glass microspheres. A decline in glass transition temperature and storage modulus was observed as a result of moisture absorption. The tensile results of the specimens exhibited a decrease of 13% and 9% in distilled water and seawater solution, respectively when compared with unaged samples, respectively. The flexural results of the aged composite specimens demonstrated a reduction of 24% and 11% in distilled water and seawater solution, respectively when compared with unaged samples. The findings also show that the influence of moisture on the modulus is less pronounced compared to its effect on strength under both environmental conditions. The micrograph results revealed a notable deterioration of the glass microsphere and the fiber/matrix interface in the moist environment. Highlights Water absorption increases with the addition of glass microspheres. Microsphere degradation and fiber/matrix debonding are the governing mechanism. Retained 89% of tensile strength of their initial properties after exposed in sea water. Increase in microsphere contents decreases the tensile and flexural strength.