Effect of Fiber Volume Fraction in Fiber Reinforcement Compaction in Resin Injection Pultrusion Process

Abstract

In the resin injection pultrusion process (RIP), the liquid resin is injected into the continuously pulled fibers through the injection slots to cause complete wetout of the fibers. As the resin penetrates through the fibers, the resin also pushes the fibers away from the wall causing compaction of the fiber reinforcements. When the fibers are squeezed together due to compaction, the resin penetration becomes more difficult; thus a resin injection pressure below a certain pressure cannot effectively penetrate through the fibers and achieve complete wetout. However, if the resin injection pressure is too high, the fibers are squeezed together to such an extent that the fiber becomes essentially impenetrable by the liquid resin. The harder it is to penetrate through the fibers, greater is the tendency of the fibers to be pushed away from the wall and cause compaction and affect wetout. In this study, the effect of fiber volume fraction on the fiber reinforcement compaction and the complete wetout is presented.

Experimental study of roving configuration’s influence on the flow field in a full-scale transparent pultrusion injection box

“…In order to compensate scarcity of experimental data and its inherent inconclusive interpretations of real pultrusion trials, two main approaches have been established for pultrusion investigations in addition to full-scale pultrusion trials:- Analytical and numerical models , ranging from rather simple analytical 1D-models for the calculation of temperature distributions within the die, considering exothermal heat generation, to complex 3D-Computational Fluid Dynamics and Multiphysics simulations for modeling the whole process, including impregnation as well as cure- and temperature-dependent viscosity development 8,17–28 - Simplified experimental representations , where specific aspects of the pultrusion process are evaluated empirically in distinctively developed experimental setups of reduced complexity 29–32 …”

“…- Analytical and numerical models , ranging from rather simple analytical 1D-models for the calculation of temperature distributions within the die, considering exothermal heat generation, to complex 3D-Computational Fluid Dynamics and Multiphysics simulations for modeling the whole process, including impregnation as well as cure- and temperature-dependent viscosity development 8,17–28…”

A Novel Z Profile of Pultruded Glass-Fibre-Reinforced Polymer Beams for Purlins

“…The trial, especially for the Z 60-40 , has yielded good results: the tensile properties were observed under the design requirements. When making pultruded composites, some researchers may use fibre with volume fractions from 40-80%, depending on the production methods [50,51]. The greater the amount of reinforcement, the higher the strength and stiffness of the resulting composite.…”