Finite Element (FE) Prediction of Hole Characteristics and Material Removal Rate for Laser Beam Percussion Drilling of Inconel 718
S. Mishra and V. Yadava
Here we deal with the simulation of laser beam percussion drilling (LBPD) process after development of finite element (FE) model based thermal model incorporating the temperature dependent thermal properties, optical properties, phase change phenomena and effect of change in nozzle stand-off distance. Initially, transient temperature distribution in the thin sheet of Inconel 718 is simulated which is further utilized to predict the hole taper, heat affected zone (HAZ) and material removal rate (MRR). The predicted values of hole taper have been compared with the self conducted experimental values. It is found that the increase of pulse width and peak power increases the hole taper, HAZ and MRR whereas the increase of pulse frequency reduces the hole taper and extent of HAZ but enhances the MRR. It has also been observed that the thickness of sheet play a vital role in determining the quality of a laser drilled hole.
Keywords: Nd:YAG laser, Inconel 718, laser beam percussion drilling (LBPD), finite element (FE) model, hole-taper, heat affected zone (HAZ), material removal rate (MRR)