Characterization of the void content and laminate quality of fiber‐reinforced plastic composites manufactured using the resin spray and compaction method

Abstract

AbstractVoid fraction and fiber volume fraction (FVF) are among the most important parameters determining the quality of fiber‐reinforced plastic products. Most of the voids in liquid composite molding–manufactured composites are directly related to the viscous matrix (resin) flow through the porous medium (fiber) during impregnation. In this investigation, a different method, resin spray rather than injection was used to reduce the resin's flow path, which resulted in low void content and higher FVF. The resin was sprayed on the surface of the preform, and compaction was applied to infiltrate the resin towards the thickness. Sample laminates were manufactured, and computer tomography scanning was applied to diagnose void content and laminae quality. The images collected from the scanner were analyzed using ImageJ software. Effects of compaction pressure and compaction speed were characterized. According to the investigation, compaction speed was the key factor in determining a laminate's void content. Only 1.5% void fraction was integrated with a compaction speed of 1 mm/min and a compaction pressure of 100 KPa. On the other hand, compaction speed has less of an impact on a laminate's FVF.Highlights The void fraction of a composite is reduced via the spray and compaction method. Fiber volume fraction is not much affected by compaction speed. Slow compaction speeds minimize void content. Spray compaction is a low‐cost manufacturing method.