Comparative study on the mechanical behavior of carbon weft-knitted biaxial fabrics stitched by polyester fibers and preoxidized polyacrylonitrile fibers

Abstract

The carbon weft-knitted biaxial fabrics stitched by polyester fibers and preoxidized polyacrylonitrile fibers were prepared respectively. Tensile and tearing tests of two types of carbon biaxial weft-knitted fabrics stitched by different fibers were carried out. Stressstrain and load-displacement curves were obtained according to the testing data. The highspeed camera was employed to observe the whole testing process and series of still images were picked up according to the time nodes to analyze the meso-scale mechanism of the extension and displacement of tows on oriented layers and stitching yarns. The properties of the two fabrics were compared based on the research of the stitching yarns mechanical performance. The researching results indicated that preoxidized polyacrylonitrile fiber exhibit higher mechanical behaviors, and its fabric bond displays excellent performance.

Process-Induced Distortions Characterization of MBWK Fabric Reinforced Composite Helmet Shell

“…The MBWK fabrics, a member in the non-crimp fabrics (NCFs) family, of good formability on curved molding surfaces and of high property-to-cost ratio, can behave as reinforcements for the composite plate and shell structures [28]. The three-layer-connected biaxial weft knitted fabric is chosen for this experiment, as the structure shown in Figure 1, where the stitching system structure is 1 + 1 rib, which has good stretch property and can provide adequate space for inserting yarns shearing [29][30][31], and the inserting yarns are parallel and straight, hence the utilization rate of high performance fiber is over 90% [32]. In addition, the various type of inserting yarns hybrid ratio lend the MBWK fabric flexible designability [33].…”