Optimization of Process Parameters in Drilling of GFRP Composites Drilled by an End Mill

Abstract— Due to the superior physical and mechanical properties Glass fiber-reinforced (GFRP) composite materials are very attractive for applications like aerospace and air craft structural components. This results a large number of research papers on machining of these composite laminates. Out of all the machining operations, most commonly used operation is drilling. However, drilling operation is hard to carry out due to drilling–induced delamination. To increase drilling efficiency of GFRP composite laminates with the least waste and damages, it is essential to understand the drilling behavior by conducting a large number of drilling experiments and drilling parameters such as feed rate and spindle speed should be optimized. This paper presents delamination study of composite materials by conducting drilling experiments using Taguchi’s L25, 5-level orthogonal array and Analysis of variance (ANOVA) was used to analyze the data obtained from the experiments and finally determine the optimal drilling parameters in drilling GFRP composite materials. Experiments were also conducted to determine whether varying feed & spindle speed during drilling could reduce the delamination.