Glass flakes for enhancing mechanical properties of glass/epoxy composites

The purpose of this study is to improve composite mechanical properties by reducing the degradation induced by seawater in glass fibre/epoxy composites. To do this, glass flakes (50 µm in size) were placed on the surfaces of the glass fibre/epoxy composite material using various ratios (5%–15%). Glass flakes were introduced into composite materials that were exposed to seawater for a period ranging from 0 to 12 months, and changes in bending, tensile, impact, compression, and compression after impact strengths were assessed. Flexural tests revealed that the gel coat and glass flakes increased their loads by up to 24% and 23% after 6 and 12 months of water immersion, respectively. Tensile tests indicated that lower tensile strength loss occurred as the glass flake ratio rose. As the immersion duration increased, the effect of glass flakes became more evident in terms of tensile strength. Composites containing glass flakes showed greater impact strength load values in both 20 and 30 J impacts compared to the control sample. The use of glass flakes improved the residual strength values because it prevented water penetration. The control sample retained up to 50% of its compressive strength, while the 15% glass-flake reinforcement promoted retention to 56%.