Influence of Gas Environment on Structure, Morphology and Corrosion Rate of Laser Irradiated Vanadium

Vanadium samples were irradiated with Nd-YAG laser in vacuum, argon, oxygen, helium, and nitrogen environments to investigate changes in the structural, morphological, and electrochemical properties of the material. Irradiation was performed for 100 laser shots with a pulse energy of 150 mJ, a pulse width of 6 ns, and a repetition rate of 10 Hz. X-ray diffraction study revealed that the largest crystallite size was found in the case of Vanadium irradiated under helium, while the smallest crystallite size was observed in the nitrogen environment. The preferred orientation of the Vanadium remained unchanged in different gas environments. The surface morphology of the laser-irradiated Vanadium displayed cones, bubbles, cracks, cavities, droplets, grooves, dips, micropillars, ripples, and wave-like structures. The surface hardness of the Vanadium irradiated with laser in nitrogen was higher compared to the other samples. Electrochemical tests in 0.9% NaCl solution showed a significant decrease in the corrosion rate of the material irradiated in the presence of helium gas. This decrease in the corrosion rate is attributed to microstructural changes such as surface refinement.