Liquid motion in laser pulsed Al, Co and Au films
Liquid motion in laser pulsed Al, Co and Au films
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DOI：
10.1016/s0169-4332(96)00912-9
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发表时间：
1997-02-01
影响因子：
6.7
通讯作者：
Nink, T
中科院分区：
文献类型：
--
作者：
Bostanjoglo, O;Nink, T
通过时间分辨电子显微镜观察了纳秒激光脉冲在“真实的”Al和Au薄膜中产生的熔体动态，其温度高达熔化温度的两倍，热梯度为10（9）K/m。熔体通过以下方式不稳定：（1）在10 ns内蒸发杂质分子的反冲;（2）热毛细流动，在100 ns内驱动液体向上或向下激光施加的热梯度，这取决于预处理;（3）热毛细振荡，其建立时间小于或等于50 ns，频率为5-10 MHz。纯材料的表面相关参数不能预测含有原生杂质的金属薄膜中的流动效应。
The dynamics of melts with temperatures up to twice the melting temperature and thermal gradients of 10(9) K/m, as produced by nanosecond laser pulses in 'real' Al and Au films, were visualized by time-resolved electron microscopy. The melts were destabilized by (1) recoil from evaporating impurity molecules within 10 ns; (2) thermocapillary flow, driving the liquid within 100 ns up or down the laser imposed thermal gradient, depending on the pre-treatment; (3) thermocapillary oscillations with build-up times less than or equal to 50 ns and frequencies 5-10 MHz. The flow effects in metal films with native impurities cannot be predicted with surface relevant parameters of the pure material.