Study on the effect of hygrothermal aging on the properties of three-dimensional woven composite materials with damage

Abstract

This study analyzed the hygroscopic characteristics and mechanical properties of three-dimensional woven composite materials under 70℃/85%RH conditions and with the presence of damage. First, the materials underwent hygrothermal aging tests, including analysis of mass change, moisture absorption rate, SEM microstructure, Fourier-transform infrared spectroscopy (FT-IR), dynamic mechanical analysis (DMA), and subsequent open-hole tensile and compression strength tests under different environmental conditions. Finally, macroscopic failure analysis was conducted. The results showed that as the hygrothermal aging time increased, the moisture absorption rate increased and the fiber surface became smoother, while the degree of debonding between the fiber and matrix increased. The open-hole tensile and compression strength of the composite material decreased as the aging time extended, and the environmental temperature had different effects on open-hole tensile and compression strength.