脉冲激光烧蚀块状靶材的双动态界面研究

STUDY ON THE TWIN DYNAMIC INTERFACES OF BULK TARGET IRRIDIATED BY PULSED LASER 

给出脉冲激光作用块状靶材的烧蚀模型 .根据能量平衡原理 ,导出烧蚀面的位置随时间的变化关系 .利用绝热近似、温度连续性条件和能量平衡原理来获得烧蚀面与固液相界面边界条件 .结合热传导方程 ,利用精确解与积分近似法相结合的方案 ,给出固液两相的温度分布与时间和位置的变化关系 ,以及固液相界面的位置随时间的变化规律 ,并与已有的理论和实验结果进行比较 .最后以铝靶为例计算模拟了激光烧蚀的全过程计算 .

The ablating model of a bulk target irradiated by a pulse laser is set up. Using the simple energy balance considerations,the relationship of the ablating surface's location with the time is derived. By adiabatic approximation,the continuous-temperature condition and conservation of energy,we find out all the boundary conditions. By using the combination of analytical method and integral-approximation method,and solving the heat now equation, the temperature distribution of soild and liquid phases' as functions of time and location are obtained,the interface of solid and liquid phase is also derived. In addition,the results are compared with other published data. Finally,most of the calculated results present are on excimer-laser irradiated target Al,although the calculations can be easily extended to laser irradiation of other targets.