Investigating the integral-structure of HRBP/CHP/CF consisting of nonwoven flexible inter/intra-ply hybrid composites: Compression, punctureresistance, electromagnetic interference shielding effectiveness

This study fabricated the integral-structure flexible inter/intra-ply hybrid composites, composed of HRBP cushioning layer and inter/intra-ply hybrid laminates surface-reinforcements through needle-punching and thermal-treating. Effects of the factors, including HRBP/CHP blending ratio, needle punching frequency and laminating sequence, on the compression, puncture resistance and electromagnetic interference shielding effectiveness (EMI SE) of flexible inter/intra-ply hybrid composites were investigated. An integral memory model on the compressive loading of non-woven structure was designed based on Poisson distribution, on which the numerical analysis was based to predict the compressive resistance and hysteresis loss. The support factor was greater than 8.2, and the highest value was recorded at a fiber blending ratio of 7H/3C and needle-punching frequency of 100 S/minute. The predicted compression energy loss was in good agreement with the actual value. The puncture resistance was enhanced with an increase in HRBP fiber blending ratio and a decrease in needle-punching frequency. With an electromagnetic wave frequency ranging from 2.0 to 2.5 GHz, the hybrid composites had excellent electromagnetic shielding effect. The EMI SE of the hybrid composites exhibited similar curve in different wave band when needle-punching frequency was enhanced. The hybrid composites with a cushioning center-ply and double hybrid-laminates cover-plies exhibited the highest EMI SE.