抄録
Precision micro-machining without crack and with narrow heat affected zone is required in order to use high-performance material. For this purpose, it is expected that higher harmonics of Nd:YAG laser could perform precision micro-machining by its high photon energy. However, even using harmonics of Nd:YAG laser, heat affected zone is inevitable due to the plasma generation. In order to reduce the influence of plasma, it is important to understand the generation mechanism of plasma. Therefore, the laser induced plasma was observed by high-speed shutter camera, and the influence of laser wavelength on machining characteristics was investigated.
