LASER-HEATING MECHANISM INCLUDING EVAPORATION PROCESS INITIATING LASER DRILLING

A laser heating mechanism initiating the drilling process is examined. The study includes conduction and convection effects and assumes a st eady-state evaporation process. This enables estimation of the limits of the Fourier theory in laser drilling applications. Using the model described in the analysis, maximum temperature attained inside the mat erial, nucleation, explosion process and drilling efficiency are predi cted. The results obtained from the present work for the vapor front v elocity are compared to those obtained from previous experiments. In a ddition, a laser drilling experiment is carried out while monitoring t he surface evaporation process. This enables correlation of the theore tical results with the experiments.