Permeability testing and mechanism analysis of aramid fiber hybrid fabrics

Aramid fiber composites have exceptional mechanical and insulating properties and are used in ultra-high-voltage power transmission. Fabric permeability is crucial for controlling composite defects. At present, the effective method to improve the permeability of aramid fibers is the hybridization of fiber fabrics. This study investigates permeability tests and impregnation mechanisms of aramid fiber fabric and its hybrid fabric. The permeability of the aramid fiber fabric and the hybrid fiber fabric was measured using a camera and a pressure sensor. The permeability of the fabric was analyzed by observing the structure, surface topography, dynamic contact angle, and surface free energy. The results show that the dynamic contact angle can be reduced and the surface free energy can be increased by hybridizing the fibers and the wettability of the fiber fabric is improved. Compared to an aramid fiber fabric, the in-plane permeability of aramid/glass fiber interlayer hybrid fabric increases by 36.19%, while the in-plane permeability of aramid/glass fiber intralayer hybrid fabric increases by 64.97%. The out-of-plane permeability of aramid/glass fiber interlayer hybrid fabric increases by 16.79%, while the in-plane permeability of aramid/glass fiber intralayer hybrid fabric increases by 30.1%. This study offers theoretical guidance for aramid fiber composite manufacturing and simulation input parameters.