Experimental analysis of glass fiber reinforced epoxy composite with calcium carbonate (CaCO3) as filler for automobile body panel application using multi-objective optimization

Composite materials made from glass fiber-reinforced epoxy are increasingly being applied in the automotive sector. These advanced materials offer a unique combination of lightweight properties, high strength, and durability, making them ideal for enhancing vehicle performance and fuel efficiency. In this study, a composite was developed using the hand lay-up method, incorporating glass fiber as reinforcement, epoxy as the matrix, and calcium carbonate as a filler. The properties examined were tensile strength, compressive strength, impact strength, and water absorption. To optimize the input parameters, the Taguchi L9 orthogonal array was employed. The results indicated that specimens with 6 wt% calcium carbonate achieved the highest tensile strength of 130.58 MPa. Maximum compressive strength was observed in samples with 10 wt% calcium carbonate, yielding 47.54 MPa, while peak impact strength was also recorded at 6 wt%, measuring 12.96 kJ/m². Further, we applied a Taguchi-based grey relational analysis for multi-objective optimization. The confirmatory tests demonstrated notable improvements achieved through this method, with a 4.07% increase in tensile strength, a 20.37% enhancement in impact strength, and a slight 3.66% decrease in compressive strength.