不同结构UHMWPE纤维纬编针织复合材料弯曲性能

Bending Properties of UHMWPE Fiber Weft Knitted Composites with Different Structures

以超高分子量聚乙烯(UHMWPE)纤维为原料,在电脑横机上编织出较理想的UHMWPE纤维纬平针、罗纹、畦编针织结构织物。采用VARTM工艺、(0°,90°)3s铺层方式成功制备了六层纬平针、六层罗纹以及六层畦编UHMWPE纤维纬编针织复合材料板。对三种复合材料板的弯曲性能及其影响因素进行研究,比较并分析其弯曲应力-挠度变化曲线和破坏形式。结果表明:三种UHMWPE纤维纬编针织结构增强复合材料的弯曲应力-挠度曲线具有非线性特征,曲线均类似于抛物线;其中,纬平针织结构复合材料的弯曲强度最大,罗纹次之,畦编最小;承受弯曲破坏的主要是树脂基体,没有出现增强体断裂、撕开等现象,表明由高强聚乙烯纤维制成的增强体材料具有较强的韧性与较高的强力。

Three kinds of weft knitting structure fabrics （weft plain, rib, cardigan ） based on ultra- high molecular weight polyethylene （UHMWPE） as raw materials were knitted by computerized flat knitting machine. Each kind of fabric was laminated from six layers into composite material plates re- spectively, which is laid up in （0°, 90 °） 3s by VARTM. The bending performance and the influencing factors of the three kinds of fabrics were studied, which were followed by the comparison and analysis of the stress-deflection curve and the failure mode. The results indicate that the bending stress-deflec- tion curve of three kinds of UHMWPE weft knitting structure composites has nonlinear characteristics and the curves are all similar to a parabola; the bending strength of weft plain knitted fabric laminated plate is the best, rib is the second, cardigan is the last. This shows that the technological parameters of different fabric structures have a great influence on the bending performance of composite materi- als. The bending failure mainly occurs on the resin matrix, and no fracture, tearing occurs on the re- inforcement. This also shows that the reinforcing material made by UHMWPE fiber has strong tough- ness and high strength.