Coupling effect of temperature and braided angle on compressive behaviors of 3D braided carbon-epoxy composite at low temperature

This paper reports the influence of temperature and braided angle on compressive behaviors of 3D braided carbon fiber-epoxy composites. The compressive behaviors of the 3D braided with three braided angles (26 degrees, 35 degrees and 48 degrees) were tested at various temperatures (-100?, -50?, 0?, 20?). The compressive damage morphologies were observed with SEM photographs. It was observed that the temperature and the braided angle have significant effect on the longitudinal compressive behaviors of 3D braided composites. The overall effect of braided angle on the 3D braided composites was greater than the temperature. The influence of the braided angle on the compressive behaviors is from the yarn orientation angle, while the influence of the temperature is from the temperature-dependent behaviors of the epoxy resin. Under low temperatures, the 3D braided composite behaved as brittle material and the compressive damage was easier than that of room temperature. The changes of yarn trajectory also led to generate the damage zone, especially in the edge and surface regions of the 3D braided composites.