芳纶捆绑对纬编双轴向多层衬纱织物增强环氧树脂复合材料层间性能的影响

将芳纶作为捆绑纱制备纬编双轴向多层衬纱(MBWK)织物增强环氧树脂复合材料,研究了MBWK织物增强环氧树脂复合材料层间性能及芳纶捆绑纱对其层间性能的影响。通过三点弯曲和短梁剪切测试,得到MBWK织物增强环氧树脂复合材料的弯曲性能和层间剪切性能,并通过Aramis V6三维场应变测量系统观察实验过程中层间应变变化。与传统涤纶低弹丝捆绑的MBWK织物增强环氧树脂复合材料相比,芳纶捆绑MBWK织物增强环氧树脂复合材料的弯曲性能和层间剪切性能明显提升,弯曲强度和层间剪切强度分别提高了14.21%和12.70%;弯曲模量提高了25.49%。芳纶捆绑MBWK织物增强环氧树脂复合材料在受到面外载荷时,纵向应变(Epsilon X)和层间剪切应变(Epsilon XZ)在中性面区域内较大,且在受到面外载荷时,芳纶捆绑纱起到有效抑制复合材料分层的作用。

Effect of aramid bundling yarn types on interlaminar properties of multilayered biaxial weft knitted fabric reinforced epoxy composites

The interlaminar properties of multilayered biaxial weft knitted (MBWK) fabric reinforced epoxy composites were studied by using aramid yarns as bundling yarns. The interlaminar properties of MBWK fabric reinforced epoxy composites and the effects of aramid bundling yarn on the interlaminar properties were analyzed. The bending and interlaminar shear properties of the MBWK fabric reinforced epoxy composites were obtained by three-point bending and short-beam shear tests. The interlaminar strain changes were observed by Aramis V6 digital image correlation system. Compared with the traditional MBWK fabric reinforced epoxy composites bonded with polyester filaments, the bending and interlaminar shear properties of the MBWK fabric reinforced epoxy composites bonded with aramid fibers are improved significantly with the bending strength, interlaminar shear strength and the bending modulus increment of 14.21%, 12.70% and 25.49%, respectively. The longitudinal strain (Epsilon X) and interlaminar shear strain (Epsilon XZ) of MBWK fabric reinforced epoxy composites bound with aramid fibers are larger in the neutral location when the composites are subjected to the out-of-plane loads. And aramid yarns play an effective role in restraining the delamination of composites when subjected to out-of-plane loads.