Abstract: The paper presents the results of theoretical and experimental investigation on the process of metal boiling initiated by pulsed laser beam, with a transparent layer on the metal surface that provides the impedance acoustic load. The theoretical analysis shows that with the squeezed surface, when the energy thresholds of metal boiling essentially depend on laser pulse shape and duration, considerable overheating of metal is possible in the course of laser pulse. In the experiments on mercury, nonlinear variations in the photoacoustic signal were registered that are due to vapor pressure contribution under the excess of boiling thresholds. The experimental values of mercury boiling thresholds under pulse laser heating agree well with theoretical estimates. !9
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