Compressibility and permeability of fiber reinforcements for pultrusion

The aim of this work is to characterize fiber reinforcements used in the pultrusion process in terms of compressibility and permeability. The compressibility of single and multiple layers of reinforcement are obtained by applying a defined compression load ramp to the material positioned into a tool mounted to a universal testing machine. The results are used to estimate the number of rovings which can be fed to the process for a given die cross section as well as quantity and type of planar reinforcements. A tool with a central injection nozzle is employed for the permeability measurements. The tool allows the monitoring of unsaturated as well as saturated flow through pressure transducers located at different positions within the cavity. The principal permeability parameters in the plane K1 and K2 are obtained. The results provide important input data for pultrusion process simulations.