Laser treatment of alumina based ceramics using second harmonics of Q-switched Nd:YLF laser

This paper is dedicated to laser engraving and drilling process of the alumina ceramics. Both processes are characterized by exquisite features in comparison with conventional ones. The main benefits are high speed, high precision and good quality along with flexibility. Moreover ceramics are hardly processed by conventional methods due to their high hardness and brittleness. Analysis of Nd:YLF laser engraving alumina ceramics concerning the influence of parameters like output power, processing speed and number of runs on various mark characteristics was carried out. Mark width, mark depth and contrast were evaluated and it was found out that output power determines both mark depth and width. Higher power caused generation of deeper and wider marks characterized by high contrast. Processing speed controls the overlapping of spots and the laser-material interaction time, thus having impact on the mark depth and contrast. Laser drilling was examined in dependence of output power that had crucial effect on the hole depth not on diameter. The research clarified that high output powers are necessary for producing deep holes so as high output powers together with low processing speeds are the optimal parameters to get maximal mark width and depth with satisfactory quality during engraving. Samples were analyzed using confocal microscope and contact profilometer.