Study on Laser Drilling Process of Solid Metal on Its Liquid

Abstract

The state where the solid layer exists on the liquid, was simulated by placing a thin sheet of solid metal on the liquid one, and laser irradiation experiment was conducted by using the simulated setup. Moreover, thermal fluid analysis was performed to understand the detail of drilling phenomena during the laser irradiation for the solid layer on the liquid. The high-speed observation revealed the time when the penetration hole was formed for the solid metal, and the intensity of reflected laser from the specimen changed just after the formation of penetration hole for solid metal on liquid one. The thermal fluid analysis indicated that the specific change of reflected laser intensity related to the detection of liquid surface. It was suggested that the exposed liquid surface under the solid layer could be detected by measuring the specific change of reflected laser intensity.