飞秒激光烧蚀铝片的热弛豫效应模拟与实验研究（英文）

Thermal relaxation in ablation process of aluminum sheet by femtosecond laser

研究了在不同能量密度的单脉冲飞秒激光下烧蚀铝片的过程。通过分析基于双温模型有限差分法所模拟出的数据图,并结合飞秒激光烧蚀实验的结果,从而研究不同激光能量密度与铝片烧蚀之间的联系。研究表明:飞秒激光能量密度与飞秒激光烧蚀的关联,而实验所测的结果进一步表明了提升飞秒激光能量密度对加工铝材料的加工效率以及加工质量的影响。通过研究和实验结果能够得出随着飞秒激光能量密度的增加,飞秒激光烧蚀期间铝材料的热弛豫过程将加长,烧蚀强度也将有所增加,同时铝材料加工后得出形貌质量也将有所提高,这个结论对于飞秒激光烧蚀金属材料的研究具有一定的意义。

In this study,the ablation of aluminum sheets under single pulse femtosecond laser with different ener-gy densities was studied.To simulate data map by using finite difference method and study the relationship be-tween laser energy density and ablation,the femtosecond laser ablation experiment results were combined with two-temperature model.The ablation process of femtosecond laser belongs to non-equilibrium ablation.According to the simulated data,the surface electron temperature and lattice temperature could be directly observed during the ablation process of aluminum sheets.The thermal relaxation in the whole laser-ablation process was further-more studied.The electro acoustic interaction under femtosecond laser ablation with different energy densities was studied.The correlation between energy density and femtosecond laser ablation was revealed based on the simula-ted results.Through analysis of the experimental data,it could be concluded that the femtosecond laser energy density,the processing efficiency and the quality of the processed aluminum materials were the three significant factors.Moreover,it could be found that with the increase of femtosecond laser energy density,the thermal relax-ation process of femtosecond laser ablation was elongated,the ablation strength was enhanced to some extent,and the appearance quality of the processed materials could be improved.Therefore,it is of great importance to study the femtosecond laser ablation of materials.