BMI RESIN COMPOSITES REINFORCED WITH 3D CARBON-FIBER FABRICS

A unique characteristic of three-dimensional fabric composites is the through-thickness reinforcement, which is responsible for reducing interlaminar failure. In this study, bismaleimide (BMI) resin was reinforced with three-dimensional fabrics. The purpose of this paper is to investigate the effect of various structures on such physical properties as tensile strength, flexural strength and short-beam shear strength. Impact strength and the effect of temperature on mechanical properties are also discussed. Experimental results show that the tensile strength and flexural strength of three-dimensional fabric composites increase with the contracting of the spacing between two Z-direction yam bundles, and the strength of 3D structures is greater than that of 5D structures. Since the Z-directional fibers have the effect of resisting crack propagation, the short-beam shear strength of three-dimensional composites is greater than that of 2D composites. The impact properties of 3D composites are also better than those of 2D composites, the effect of the 3D reinforcement having been found to give a 1.66-fold increase in maximum load and a 1.68-fold increase in the total impact energy.