Modeling of Hygrothermal Damage of Composite Materials

Composite materials have been used extensively in various applications, such as mechanical engineering, aerospace engineering, and aviation thanks to their interesting mechanical properties. However, a substantial drawback in the use of such composite materials is that they absorb a significant amount of moisture when exposed to severe hygrothermal conditions. This factor dramatically affects the composite material’s various physical and mechanical properties. This paper proposed a new model to predict the amount of moisture absorbed by a composite polyester/glass fiber composite material before and after hygrothermal damage. Two damage models were proposed and implemented in ABAQUS. A numerical simulation was used to estimate hygrothermal stresses in a composite plate. The results showed that the moisture absorption followed a Fickian behavior; if the temperature was low, the plate would be damaged, but the moisture diffusion rate accelerated when the hygrothermal parameters (temperature and humidity) were high. Additionally, the magnitude of residual stress, which was at its maximum at the beginning of the absorption, started to decrease until reaching zero when the plate was saturated.