Characterisation of moisture absorption effects on the strength of composite materials

Abstract

In the present work, the variation of the tensile strengths of various polymers and polymer composites due to moisture ageing is investigated. The stacking sequences of the composites include 0o, 90o, ±45o and quasi-isotropic laminates. The variation in the strength of material is then fitted using a residual property model. Results show that the proposed model characterises well the variation in the strengths that exhibits a typical trend, where there is no obvious scattered data. In fibre dominated laminates (0o), the degradation parameter seems to be influenced by the type of material, whereas for matrix dominated laminates (90o), ageing temperature appears to be the dominant factor that affects the degradation trend. As for [±45]2S and adhesives, exponential decay trend is observed. This model could be further improved to include the material and temperature factors.