Influence of defined amount of voids on the mechanical properties of carbon fiber‐reinforced plastics

Abstract

The fault‐free fabrication of fiber‐reinforced plastics (FRPs) is a big hurdle for textile and composite manufacturers. Voids are generated during the infiltration process of FRPs, which then reduce the mechanical performance of FRPs. This paper describes the effect of defined amount of voids on the mechanical properties, such as tensile, bending, impact and inter‐laminar shear strength of FRPs. The defined amount of voids in carbon FRPs are produced by a newly developed process—mixing of a foaming agent with resin system during the infusion process. The utmost advantage of this process is simple, time‐saving and reproducible. The produced FRPs from this process can be utilized for the validation of ultrasonic testing of FRPs. Four types of FRPs with six carbon layers are fabricated by a vacuum assisted resin infusion process. Carbon fibers are chosen in this study because of their growing market potential. Then, the mechanical properties of the produced carbon FRPs are tested. Besides the mechanical testing, the microscopic testing and ultrasound testing is executed to qualitatively analyze the length and distribution of produced voids. Results reveal that the mechanical properties of carbon FRPs reduce by an increase in defined amount of voids. POLYM. COMPOS., 40:E1049–E1056, 2019. © 2018 Society of Plastics Engineers