Simulation and experimental study on laser drillingof nickel-based alloy with thermal barrier coatings

We investigated drilling in a nickel-based alloy covered with thermal barrier coating using a millisecond-pulsed laser and made a comparison between simulation and experimental data. We used the finite element model with multilayer structure in accordance with the thermo-physical performance parameters of the thermal barrier coating, the bond coating layer, and the nickel-based alloy. We then uploaded the laser on the coasting surface by means of Gaussian thermal density. It was possible to determine both the diameter and depth of microhole changes with increasing pulses using a temperature distribution analysis. The obtained surface profile is in agreement with the experimental results. A stress distribution cloud chart of microholes was generated following a coupling analysis of thermal stress. Post-processing and analysis of the simulation made it possible for us to understand the formation mechanism of microholes and cracks. Furthermore, the simulation results can serve as the basis for a pulsed laser drilling study and crack analysis of multilayer materials.