Gas dynamics of laser ablation: Influence of ambient atmosphere
Gas dynamics of laser ablation: Influence of ambient atmosphere
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DOI：
10.1063/1.1286175
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发表时间：
2000-09
影响因子：
3.2
通讯作者：
A. Gusarov;A. Gnedovets;I. Smurov
中科院分区：
文献类型：
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作者：
A. Gusarov;A. Gnedovets;I. Smurov
提出了一个激光烧蚀的两阶段二维气体动力学模型。该过程的初始一维阶段与激光脉冲作用下的烧蚀羽流形成有关（持续时间约为10 ns;能量密度约为几J/cm 2;激光光斑直径约为1 mm），并描述了靶的加热、熔化和蒸发、Knudsen层中的靶-蒸气相互作用以及蒸气动力学。最终的2D阶段负责形成烧蚀材料的能量和角分布。结果表明，激光蒸发材料膨胀羽流周围的环境气体受到了相当大的压缩，在未扰动的环境气体中形成了激波阵面，激波后的压缩环境气体压力可能比环境气体压力高得多。然而，在低于100 Pa的研究环境压力下，它仍然远低于激光蒸发过程中的蒸汽压。因此，th…
A two-stage two-dimensional (2D) gas-dynamic model of laser ablation in an ambient gas atmosphere is proposed. The initial one-dimensional stage of the process is related to the ablation plume formation under the action of a laser pulse (duration of the order of 10 ns; fluence about several J/cm2; laser spot diameter about 1 mm) and describes heating, melting, and evaporation of the target, the target–vapor interaction in the Knudsen layer, and the vapor dynamics. The final 2D stage is responsible for the formation of the energy and angular distributions of the ablated material. Considerable compression of the ambient gas around the expanding plume of the laser-evaporated material and a shock front propagating through the undisturbed ambient gas are found. The pressure of the compressed ambient gas behind the shock may be much higher than the ambient one. However, at the investigated ambient pressures below 100 Pa, it remains still much lower than the vapor pressure during laser evaporation. Therefore, th...