Tensile and Water Absorption Properties of FRP Composite Laminates without Voids and with Voids

Abstract

This project work is done to know the effect of voids in the FRP composites. The FRP composites are fabricated with hand molding process. First few samples are fabricated with the normal procedure. The sample size is as per ASTM D 638. These samples were assumed to be free of voids. Few more samples are fabricated by hand molding process with the introduction of voids. While fabricating the FRP composite laminates, the water soaked gel balls of sizes ½ mm, 1 mm, 1.5 mm and 2 mm were introduced at the centre of the sample. When the sample is dried the gel balls will reduce to a size of 1/10 mm leaving the remaining size as voids. In this way it is assumed to be the voids are introduced while fabricating the FRP composites. The tensile tests are conducted on both samples i.e. the samples without voids and also on the samples with voids. The examination of the stress-strain graph will show the effect of the voids on the tensile strength.The stress – strain graph of the samples without voids is nearer to the straight line, but the stress – strain graph of the samples with voids is not the same, it is showing some curvature. The tensile strength decreased with the increase of void size. Similarly the samples with voids show more water absorption than the samples of without voids.