双轴向衬纱纬编玄武岩纤维复合材料弯曲性能

经纬纱和针织纱分别选用不同线密度的高模高强玄武岩纤维, 以不同衬纱方式编织出机织针织复合(CWK)织物和多层双轴向纬编(MBWK)织物, 并以其作为增强体, 采用真空辅助树脂传递模塑工艺制备了玄武岩纤维/乙烯复合材料。对两种复合材料0°、 90°和45°方向的弯曲性能进行测试, 分析比较了弯曲应力-应变特征曲线及纱线强度。结果表明: 两种复合材料具有较好的弯曲性能, 0°和90°方向的弯曲性能均优于各自45°方向的, 弯曲应力-应变曲线均表现出一定的塑性破坏特征; MBWK织物增强复合材料0°和90°方向的弯曲性能又分别高于CWK织物增强复合材料0°和90°方向的弯曲性能; 复合材料中经纱和纬纱的屈曲程度不同, 致使MBWK织物增强复合材料的比模量和纱线强度均高于CWK织物增强复合材料, 两种复合材料的弯曲性能受不同衬纱方式的影响, 而两种复合材料试样的弯曲破坏形态相近。研究结果为双轴向衬纱纬编玄武岩纤维复合材料的应用提供了参考。

Bending properties of bi-axial weft-knitted basalt fiber fabric reinforced composites of different ways of inserted yarn

Co-woven-knitted (CWK) fabric and multi-layered biaxial weft knitted (MBWK) fabric were produced by different ways of inserted yarn, using high tenacity and high modulus basalt fiber filaments with different linear density as warp, weft and stitch yarns. Then the fabrics were used for preparing the basalt fiber/ethylene composites by vacuum assisted resin transfer molding process. The bending tests were carried out in 0?, 90? and 45? directions. The mechanical properties of the composites were investigated and compared by analyzing the bending stress-strain curves. The results reveal that the bending strength and the elastic modulus of the two materials in 0? and 90? directions are all better than that in 45? direction, and the curves have the characteristics of plastic fracture. The bending properties in 0? and 90? directions of the MBWK fabric reinforced composites are better than that of the CWK fabric reinforced composites. The buckling of the warp and weft yarns causes that specific modulus and strength of yarns of the MBWK fabric reinforced composites are better than that of the CWK fabric reinforced composites. The bending properties of the composites are affected by different ways of inserted yarn. Bending damage forms of the composites are similar. The results provide a reference for the application of the composites.