[23p-C205-1~11] 4.3 Lasers and laser materials processing

▲ [23p-C205-10] Multiple time-scales observation of femtosecond laser drilling of zirconia ceramics

〇(P)Yanming Zhang¹, Yusuke Ito¹, Huijie Sun¹, Naohiko Sugita¹ (1.UTokyo)

Keywords:Pump-probe imaging, Electron excitation, Plasma evolution

Due to the characteristics of high hardness and brittleness, there is always a challenge in traditional processing of zirconia (ZrO₂) ceramics such as huge cutting force and crack damage. Femtosecond laser has been successfully applied for ZrO2 ceramics machining because of its ultrashort pulse duration with high peak power. However, the unclear understanding of the ultrafast laser-material interaction mechanism in femtosecond laser drilling of ZrO₂ ceramics still limits the achievement of precision processing. In this study, the pump-probe imaging method with focusing probe beam integrated with a high-speed camera is developed to directly observe the processing phenomena inside of ZrO₂ under different timescales, including the the electron excitation, shockwave propagation, plasma evolution and the hole formation process. A set of experiments is conducted to reveal the relationship between above phenomena and laser-material interaction mechanism.The clear imaging and investigation of above phenomena contribute to revealing the ultrafast laser-material interaction mechanism and precision processing in laser drilling zirconia ceramics.