EFFECT OF MOISTURE ON FATIGUE STRENGTH OF FRP COMPOSITE

Abstract

Owing to their favourable performance characteristics, Composite materials have been gaining wide use in commercial, millitary and space applications. There is some concern, however that the mechanical properities of such materials may suffer when the -material - As exposed to moisture. Therefore in order to . utilise the full potential of Composite materials their reponse to moist environments must be known. The objective of this investigation was to determine the effect of moisture on Fatigue strength of 00/900 Woven Glass Fibre/Epoxy Composite. Axial Fatigue tests at stress ratio of 0 and 0.5 were performed on 00/900 Woven Glass Fibre/Epoxy Composite. Both dry and water pre-soaked specimens for two different periods of time were tested to assess the effect of moisture on fatigue strength. S.N. curves are obtained for two different periods of time .i.e., 15 days and 30 days pre-soaked specimens and dry specimens at stress ratio zero, and at stress ratio 0.5 for 30 days pre-soaked and dry specimens. The results show that the presence of moisture decreases the fatigue strength of the Composite.