Investigation on Drilling Behavior of CFRP Composites Using Optimization Technique

Carbon fiber-reinforced polymers (CFRPs) have been applied to various fields such as electronic printed circuit boards, aircraft brakes, automobile forks, and machine tool-damped structures due to their low density and high tensile strength. These application components required micro-hole and macro-hole in it for joining. In this research work, a comparison of the experimental investigation on micro- and macro-drill on CFRP using a vertical machining center has been carried out. The input machining control factors were spindle speed and rate of feed, whereas the quality characteristics of drilling CFRP were considered as thrust force, delamination, and overcut. Analysis of variance (ANOVA) and gray relational analysis were employed to identify the most significant factor and optimum process parameters, respectively. Microstructural defects of micro-hole and macro-hole were studied using scanning electron microscopy. Results showed that the rate of feed linearly affected the thrust force and delamination and is inversely proportional to overcut.