Study on friction and wear of preform Z-directional fiber

In order to reduce the wear and tear of Z-yarn implantation into the preform, the frictional behavior of Z-yarn during implantation into the preform was studied. According to the actual implantation conditions of Z-yarns, we designed a guiding array clamping device and a tensile force sensor to study the changes of tensile strength of Z-yarns at different implantation positions and implantation times, results show that the tensile strength of Z-yarns decreases significantly after 25 implantations at the position of 4 N friction force, and it's necessary to replace Z-yarns in time to avoid their fracture in the preform. The use of unadulterated solvent dimethyl silicone oil applied to the Z-yarns, can significantly reduce their wear, the tensile strength of Z-yarns after 60 implantations is only 5.6% lower than that of Z-yarns after 10 implantations. Design the tension control system, and when the tension is 0.46 N, the tensile strength of Z-yarns during implantation is 34.2% higher than without tension. Meanwhile, the relationship between the normal force applied to Z-yarn and the implantation length and fiber bundle width are established by combining Hertzian theory and experimental data, and the friction coefficient algorithm during Z-yarn implantation is derived by combining Howell's equation, which solves the problem that the fiber friction coefficient cannot be measured due to the complicated working condition of Z-yarn implantation. The frictional wear mechanism of yarn during Z-yarn implantation into the preform is revealed, and a method to reduce yarn wear and increase its continuous implantation number is proposed.