Fabrication of transparent advanced composites

Transparent advanced composites offer distinct mechanical advantages over other transparent materials including high specific strength and stiffness, and exceptional impact resistance due to their quasi-brittle nature. This potentially allows them to be used in large and load-bearing applications. However, there are challenges and limitations to fabricate composites with high degree of transparency due to inherent chromatic aberration and other surface and bulk defects. In this paper, a systematic approach to fabricate transparent composites using advanced glass fibers and thermoset-based resin systems is presented. It is shown that using low-cost commercial grade E-glass fibers, high transparency can be achieved. An epoxy-based resin system is developed by systematically matching the chromatic dispersion of E-glass fiber and resin. Surface and bulk defects are mitigated by developing a customized infusion-based manufacturing process. The method was successfully applied to fabricate composite samples with light transmissions up to 88%.