Flaw Analysis on the Manufacturing Process of GFRP Laminates using Wet Lay-up Method

Abstract

The flaws that occurred in the manufacturing process of unidirectional Glass Fibers Reinforced Plastic (GFRP) composite was investigated in the present study. The bonding substances used in this study are the mixture of Epoxy Resin and Epoxy Hardener. Three variations of fiber orientation were manufactured and observed in this study which are (90)4, (0)4, and (±45)4. The manufacturing process is divided into three main sections starting from preparing the epoxy, hand lay-up, and cutting the specimen into the desired geometry and dimensions. The mixing ratio of the resin and hardener suggested by the manufacturer is 2:1. The analysis results show that flaws occur when preparing the bonding substance, hand lay-up, and the cutting process. In the bonding substance process, there was a failure in the resin’s composition and mixing conditions, resulting in an uneven mixture, inappropriate mixing ratio, and trapped air bubbles. During the hand lay-up, the surface bubbles and early hardening phenomena occurred due to several manufacturing parameters such as resin viscosity, hardening time, and less than optimal rolling techniques. Besides, there is also damage due to the cutting process in the form of burnt fiber and delamination.