The design of multi-sample flexural fatigue device and fatigue behavior of glass/epoxy laminated composites

Due to fiber reinforced polymer composite materials have a brittle structure, it is important to know their behavior under dynamic loads. Therefore, it is necessary to know the S-N curve that characterizes the fatigue life of the composite material, when selecting and sizing the material. In this study, fatigue behavior of glass/epoxy laminated composites was investigated under flexural loading. For this aim, computer controlled fixed end type flexural fatigue test machine was developed and glass/epoxy test samples were tested under flexural stress corresponding to 80%, 70%, %60, %50, and %40 of the static 3-point bending strength. In addition, the static strengths of the epoxy-laminated composites under tensile, compressive and flexural loads were also determined. It has been observed that the damage such as matrix and fiber cracks and delamination in the glass/epoxy laminated composites, which were exposed to flexural deformation. Also, it has been seen that, the developed fixed end type flexural fatigue test machine can be used to determine fatigue behavior of thin-walled composite materials.