Investigation of tool wear behavior in CFRP drilling by using different tool materials

The industrial usage of Carbon fiber reinforced polymers (CFRP) has increased significantly over the past few years due to its distinguished characteristics like great strength-to-weight ratio, fatigue resistance, superior damage tolerance, excellent corrosion resistance, etc Machining of CFRP differs from traditional machining due to its structure. This experimental study aims to investigate the effect of drill bit material on tool wear and to optimize the material selection process of twist drill bits during CNC drilling of CFRP regarding the output of tool wear, thrust forces, and torque generated during the drilling process. Four twist drill bits with dissimilar materials (i.e., HSS-4341, HSS-M2, HSS-Co, and Tungsten Carbide) having the same size and diameter (3 mm) were selected and used for CNC drilling on CFRP plates. During the drilling process, thrust forces and torque were calculated with the help of a dynamometer for each drilled hole. Moreover, the tool wear was seen and compared after the 1st hole and 20th hole for each drill bit to analyze the behavior of different tool materials toward CFRP machining. The results showed that Tungsten Carbide is the most suitable tool material for CFRP drilling as it yielded the lowest thrust forces and lowest torque for all 20 holes. Moreover, the Tungsten Carbide had the lowest tool wear among all the drill bits. These results imply that tool life can be significantly elevated if Tungsten Carbide is to be used for machining of CFRP.<br />