The Effects of the Immersion Time on the Mechanical Behaviour in Case of the Composite Materials Reinforced with E-glass Woven Fabrics

Abstract

Abstract: The paper describes aspects concerning the effects of the immersion time in water, on some mechanical characteristics of some composite materials reinforced with E-glass woven fabrics. The specimens were manufactured by reinforcing a polyester resin Copoly 7233 with both woven fabric EWR300 made of E-glass fibres and chopped E-glass fibres. The hand lay-up technology was used to manufacture the specimens with different pressures in the moulding step: low pressure and high pressure, respectively. The first of all, some specimens were immersed in water and the data regarding the moisture content were periodically recorded. Then, the wet composite specimens were subjected to the flexural test (three point method) after 3500 h of immersion and 7417 h of immersion, respectively. Finally, the experimental results obtained in case of the immersed specimens were comparatively analysed with the results recorded in case of the dried specimens subjected to the bending test too. Moreover, the mechanical characteristics of the specimens were analysed taking into account the different manufacture methods used. It is also shown a comparison concerning the results obtained in cases of the two kinds of reinforcements used.