Abstract: In recent years, due to the development of technical textiles, Thin-shell composites reinforced by directionally oriented fabrics have increasingly become a hot research topic. Inserting yarn is key component of directionally oriented fabrics, and bending deformation is the primary form in the deformation of fabrics. Therefore, the bending rigidity of inserting yarn make a large difference in conformation of directionally oriented fabrics. With the help of KES fabric style instrument, the maximum bending moment (M_max) and the fitting slope (s) are measured, which is used to characterize the bending rigidity of four commonly used high-performance yarns. The experimental results indicate: under the same Fineness, the bending rigidity of high-performance yarns is greater than that of traditional yarns, as for the four high-performance yarns in the experiment, the rank of the bending rigidity is Carbon yarn, Glass yarn, UHMWPE yarn and Kevlar yarn in descending order; the rigidity of the high-performance yarns is affected by arrangement and aggregation of filament, and decreased as the enter angle increased.

Key words: high-performance yarn, bending rigidity, axial fabric, KES-F hand tester