Reduction of weaving process-induced warp yarn damage and crimp of leno scrims based on coarse high-performance fibers

In this paper, a constructively and technologically modified leno loom is introduced, which enables for the first time the low-damage processing of coarse high-performance fibers such as heavy tows with a non-crimped warp and weft yarn system to scrims. The modified leno loom requires just a single shedding element to achieve the vertical and horizontal offset motion of the weft yarn system for pattern generation. These modifications allow the low-damage processing of coarse high-performance fibers in the warp (straight yarn) and the weft yarn systems to create leno fabrics. These leno fabrics produced with the modified loom are investigated experimentally. By means of a three-factorial analysis of variance, the influence of tensile forces operating during processing and weft density on the crimp and the tensile strength of the straight yarn is examined. It is revealed that the property degradation (tensile/breaking strength) of the straight yarn caused by the weaving process is drastically reduced to 4.2% compared to an unprocessed roving. The determined crimp of the straight yarn affected by process-inherent tensile forces is 0.1% at its maximum. Thus, the presented leno-woven fabrics offer an enormous application potential for the reinforcement of brittle matrices, such as ceramic or concrete.