The ejection of molten aluminum after the interaction with millisecond pulsed laser

Abstract

The ejection process of molten aluminum after the interaction with millisecond pulsed laser is studied through building a flow model of molten liquid after the end of pulse. Through the analytical and numerical calculations, the pressure in molten liquid near the surface, the liquid ejection duration, and the average velocity of the liquid at end of pulse can be obtained. From these calculation results and the images of ejection process recorded by the high speed camera, it can be inferred that liquid ejection after the interaction with millisecond pulsed laser is due to the release of surface energy of molten liquid. The calculation result accords well with the experimental result reported in literature, and the flow model of molten liquid can be used to further explain the ejection types in the experiment. The dependences of the ejection duration on radius of molten pool and on laser pulse power density are discussed.