Experimental Study on Tension Fatigue Behavior of Glass/Epoxy Cross-Ply and Quasi-Isotropic Laminate Composites
摘要
The fatigue behavior of composite varies depending on the type of fiber/matrix, fiber orientation, layup sequence, and manufacturing process. The purpose of this study is to examine the effect of the fiber orientation of glass fibers reinforced with epoxy matrix composites under static tensile and tension-tension cyclic loading. Using a compression molding technique, eight layers of glass fiber (in the form of unidirectional fabric) were combined with epoxy resin to manufacture the laminates. The laminates had a thickness of 3.8 mm and a fiber volume fraction of 0.55. In this study, tensile properties of unidirectional [0]8, cross-ply [0/90]2s, quasi-isotropic [0/45/90/-45]s, and transverse [90]8 laminate were experimentally determined. It was found that unidirectional laminate has the highest ultimate tensile strength, and transverse laminate has the lowest tensile strength. Tension-tension fatigue tests of cross-ply and quasi-isotropic laminates were performed at a stress ratio R = 0.1 and frequency of 3 Hz. For the S–N curve of each laminate, fatigue tests were carried out at 66.66, 50, and 33.33% of the ultimate tensile strength of the laminate. The S–N curve obtained from the fatigue experiment shows that cross-ply has higher fatigue resistance than quasi-isotropic laminate.