Analysis of nanosecond laser ablation of aluminum with and without phase explosion in air and water

Despite extensive research work, accurate prediction of the ablation behavior in the high energy nanosecond laser ablation process is still lacking, which may differ significantly depending on the laser parameters, surrounding medium, and target material characteristics. In this paper, nanosecond laser ablation of aluminum in air and water is investigated through a self-contained hydrodynamic model under different laser fluences involving no phase explosion and phase explosion. The ablation depths and profiles are predicted and validated against the literature data and experiments. In case of nanosecond laser ablation of aluminum in water, deeper crater depths are found in all the conditions studied in this work, which may be attributed to the combination effects of laser ablation and shock compression. The analysis of the shock compression in air and water indicates that the shock compression is mainly responsible for this enhancement of ablation in water.