Ablation Characteristics of Nanosecond Laser Pulsed Ablation of Aluminum

Abstract

This research presents laser ablation characteristics of an aluminum alloy after nanosecond pulsed laser ablation (PLA) with a 1064 nm Nd:YAG laser. White light interferometry and scanning electron microscopy were used to establish relationships between laser ablation characteristics and the number of pulses at different beam energies. Laser ablation features studied in this research are crater profiles, radii and depth, and extent of surface damage. An extensive damaged area around the laser ablation crater was found and is believed to be produced by the laser-induced plasma generated during PLA. Spectroscopic analysis showed that there is a correlation between the plasma formation threshold and the initiation of the plasma-affected area, and laser ablation at different angles of incidence between the beam and the sample showed a correlation between the plasma shape and the shape of the damaged area around the ablation crater. However, the variables influencing the occurrence of the plasma-affected and the extent of plasma-induced damage are not yet fully recognized and understood.