Characterization of Titanium Laser Ablation

The atomic and ionic emission lines of titanium are often studied in laser-induced breakdown spectroscopy (LIBS) investigations, partly due to the abundance and luminosity of the lines and titanium's prominence in industry. In the current study, a 13 ns pulsed Nd:YAG laser with 160mJ per pulse ablates a titanium sample in laboratory air at 10 Hz. Ti III emission lines between 232 nm and 244 nm are observed at 200 ns after laser-surface interaction, utilizing a 6 ns window. Two-dimensional images are obtained, providing spectra emanating along the height of the ablation plume. A Boltzmann plot method is implemented in order to infer electron temperature as a function of height along the plume. The hottest region of the plasma tends to be further away from the sample surface and is on the order of 16000 K.