Moisture Effects on the Material Properties of a Jute/Epoxy Laminate: Impulse Excitation Technique Contribution

Natural fibers have enormous potential and offer many advantages. However, the lack of confidence in their structural performance has limited their wider adoption. Among concerns, include susceptibility to higher water absorption. The aim of this paper is to characterize the impact of the water absorption of jute/epoxy composite material using a new approach. This material has a potential to be used in automobile industries (door panels, dashboards, etc.) and in the civil engineering (skins of the sandwich panels in the building). The method of characterization used is original and based on the impulse excitation approach. The mechanical properties identified are correlated to those obtained by classical methods of characterization such as: three points bending and shear tests. Results show clearly that the rate of water absorption decreases physical (resonant frequency) and mechanical properties (Young's modulus) of jute/epoxy laminate. At the mass saturation, we recorded a decrease in the proper frequency around 10%, and the Young's modulus in this case loses 28% to 38% of its initial value. In addition, water bath temperature had an important impact on the coefficient of diffusion as well as on the degradation of mechanical properties.