【摘 要】
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In this paper, by means of a high-sensitive optical beam deflection technique combined with electrical delay technique, shock wave and cavitation effects by laser ablation of a metal in water are investigated in detail. The system is quite handy, and of h
【机 构】
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DepartmentofAppliedPhysics,NanjingUniversityofScienceandTechnology,Nanjing210094
【出 处】
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ChineseOpticsLetters
论文部分内容阅读
In this paper, by means of a high-sensitive optical beam deflection technique combined with electrical delay technique, shock wave and cavitation effects by laser ablation of a metal in water are investigated in detail. The system is quite handy, and of high time resolving ratio and spactial precision. The experimental results present the propagation of shock waves, the expansion and contraction of laser-induced cavitation bubble in the vicinity of a solid boundary, the maximum and minimum radii during the first two oscillating cycles and the corresponding pulsation durations, the formation and development of bubble-collapse-induced shock waves. With the increase of oscillating cycles, the maximum bubble radii are decreased sharply, as well as the corresponding expanding and contracting durations. The minimum bubble radius at the first oscillation is larger than that of the second. Besides, the duration of bubble expansion is obviously longer than that of contraction at the same oscillating cycle.
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