Compressive properties and failure mechanism of three dimensional and f ive directional carbon f iber/ phenol ic braided composites

The compressive experiment s were performed for the three dimensional and five directional carbon fiber/
phenolic braided composites with different braiding angles and fiber volume f ractions in the longitudinal ( braiding)direction and t ransverse direction at different temperatures. The principal compressive properties of the composites were obtained. The influences of braiding parameters and temperature on the compressive properties were also ana2 lyzed. The macro and micro pictures of the f racture surface of specimens were observed in order to understand the deformation and the failure mechanism of the composites. The result s show that the compressive st ress2st rain curves of 3D & 5D carbon fiber/ phenolic braided composites exhibit the nonlinear characteristics and the effect s of tempera2 ture are apparent . The braiding angle and the fiber volume f raction still were the most important parameters to affect the compressive properties of the composites. The longitudinal compressive failure of the composites is very different f rom the t ransverse compressive failure.