Optimization of Machining Parameters in Drilling of Glass/Hemp/Bamboo Fibres Based Hybrid Polymer Composites

Significance of composite materials is increasing enormously in the progress of modern science and technology. The composites can be transformed into suitable components with high precision by machining, which can be used for present day applications. Drilling is crucial operation that is often used in the assembly of composite parts to obtain finished product. But the drilling induced damage may affect the performance of the composite. The present work is focused on the impact of various parameters in drilling like feed rate, spindle speed and drill diameter on surface roughness and delamination of glass/hemp/bamboo fibers embedded polymer hybrid composites. The composite is prepared by hand layup method. The drilling on composite is done on a CNC drilling machine and the maximum diameter due to delamination is measured using profile projector. To optimize drilling parameters for the sake of reducing the surface roughness and delamination factor, Taguchi method applied. The measured results are analyzed using commercially available software package Minitab19. The analysis is carried out using ANOVA (Analysis of Variance). In order to obtain best optimal conditions GRA (Grey Relational Analysis) is adopted. The results show that among all important parameters, feed rate and drill diameter are more crucial for surface roughness, whereas delamination is impacted by feed rate and speed of spindle.