Influence of Point Angle on Drill Hole Quality and Machining Forces When Drilling CFRP

Drilling optimization of woven CFRP laminates under different tool wear conditions: a multi-objective design of experiments approach

“…In general, it has been reported that increasing the point angle enhances the thrust force while the torque remains nearly constant (Heisel and Pfeifroth 2012). Increasing the point angle in conventional drills has also improved the quality of the hole in entry (less delamination), but it worsened the hole quality at the exit (Heisel and Pfeifroth 2012). The same effect has been observed at the entry of the hole in cross-ply composite materials with twist drill bits (Durão et al 2010).…”

“…Earlier studies on the influence of cuttings parameters on delamination damage in drilling woven CFRP materials show that the cutting speed would be the least influential parameter (Heisel and Pfeifroth 2012). On the other hand, cutting speed has shown some slight influence on the cutting force.…”

“…As another cutting parameter, variation of the point angle of the drill bit has shown different results on the generation of delamination and cutting force. In general, it has been reported that increasing the point angle enhances the thrust force while the torque remains nearly constant (Heisel and Pfeifroth 2012). Increasing the point angle in conventional drills has also improved the quality of the hole in entry (less delamination), but it worsened the hole quality at the exit (Heisel and Pfeifroth 2012).…”

Minimizing Drilling Thrust Force for HFRP Composite by Optimizing Process Parameters using Combination of ANOVA Approach and S/N Ratios Analysis

“…The used of 120° drill point geometry had produced the minimum delamination factor (Fd) when drilling the composite at higher feed rate. Heisel et al [4] investigated the influence of a drill tool at increased cutting speed on machining forces and drill hole quality (delamination, fraying and burr formation) of carbon fiber reinforced polymer (CFRP) composite. Their assessment shows that the quality of holes at entrance is best when using point angle >180°, while it is poor at the exit.…”

“…The research conduct on [2][3][4][5] were mostly related to drilling the conventional FRP composite materials like glass fiber reinforced polymer (GFRP) composite or carbon fiber reinforced polymer (CFRP) composite using various drill point angle, cutting speed and feed rate. None of them have studied on the drilling of hybrid fiber reinforced polymer (HFRP) composite.…”