Temperature effect on dynamic compression performance of random fibrous composites in the TTT and IP directions

This study examines the effect of temperature on the dynamic compressive performance of random fibrous (RF) composites at temperatures up to 1273 K in the through-the-thickness (TTT) and the in-plane (IP) directions, using an improved high-temperature split Hopkinson pressure bar (SHPB) system. The results revealed that in the IP direction, the RF composite presented a shear fracture mode below 1073 K and initiated multiple major cracks in the specimens at 1273 K. However, the composite showed a layered fracture mode in the TTT direction from 288 to 1273 K. The dynamic strength in both directions showed a consistent trend when observed under static loading below the critical temperature. The change in the strain-rate sensitivity (SRS) of the dynamic strength was insignificant for temperatures below the transition temperature of viscous-flow and brittle deformation of the RF composite. However, above the transition temperature, the SRS of the dynamic strength became significant.