Fatigue behavior of frp composite laminate

Composites make up a very broad and important class ofengineering materials. FRP composite materials posses the characteristicsof high stiffhess and strength to weight ratios which are desirable for awide variety of applications. The proper design of composite materials fordifferent application requires the knowledge of material behavior underdifferent load types.Therefore, the objective of this work is to investigate the tensile andthe flexural fatigue behavior of notched and unnotched GFRP (E-glassreinforced polyester resin) cross-ply composite laminate specimens(0/90/0)s. The effect of fib er volume fraction and circular notch size onthe S-N diagram of laminated specimens has been investigatedexperimentally and compared with some published formulas.The static tensile properties of this composite have been determinedexperimentally and compared with lamination theory and kelly formula forunnotched specimens and with point stress criterion and modified pointstress criterion for notched specimens. The composite laminate specimenswere made by hand lay-up technique. The fib er distribution, failure modeand fracture surfaces of GFRP composite specimens were examined byusing scanning electron microscope. The two parameter weibulldistribution function was used to describe the scatter in the tensile strengthand fatigue life data of GFRP cross-ply composite laminate specimens .