Influence of curing pressure on the compaction of carbon fiber/epoxy layers and its effects on the mechanical strength

Abstract

This work aims to investigate how the curing pressure influences the compaction of carbon fiber layers in a composite material of carbon fiber and epoxy resin applied after the gel time of the epoxy resin. As the curing pressure increases, the fiber layers are pressed against each other, which contributes to reducing the volumetric fraction of the matrix in relation to the reinforcement. Four different pressure levels are investigated in this work, 0; 2; 4; 6 bar, which are applied in flat plate molds with the aid of a hydraulic press. As effects of the fiber layers compaction this work found an increase in mechanical strength, a reduction in the mass of the specimen through the reduction of the volumetric fraction of resin, specimen’s thickness reduction and a significant increase in the specific strength of the material were observed.