Laser ablation of solid substrates in ambient air and under water is investigated. It is found that the laser ablation rate is highly enhanced by the water film. A wide-band microphone is used to detect the audible acoustic wave generated during laser ablation. Peak-to-peak amplitude of the acoustic wave recorded in water confinement regime (WCR) is greater than that recorded in ambient. It is assumed that the plasma generated in WCR induces a much stronger pressure. This high-pressure, high-temperature plasma results in a much higher ablation rate. Theoretical calculation is also carried out to verify this assumption. By proper calibration, acoustic wave detection can be used as a real-time monitoring of the laser ablation.
ASJC Scopus subject areas
- Physics and Astronomy(all)