Features of Vanadium-Surface Damage Induced by Pulsed Laser Radiation

The features of the damage of the surface layer of vanadium under the action of pulsed laser radiation are studied. Laser irradiation is carried out in air using a GOS 1001 setup in the Q-switching mode with the following parameters: flux power density q = 1.2 × 10 8 W/cm 2 , pulse duration τ 0 = 50 ns, and number of pulses N = 1–6. The typical surface damages induced by the laser pulses are found to include the melting of material, a microcrack network, a wavy relief, and drop-like particles. The central region characterized by the greatest degree of damage contains also individual drops of metal, which crystallized like a spiral. The heat-affected zone (HAZ) adjacent to the central one is damaged to a significantly weaker extent. Surface degradation increases as the number of pulses increases. Laser irradiation is revealed to change the X-ray diffraction (XRD) patterns: loss of texture, presence of vanadium-oxide signal, peak broadening, and lattice parameter increase (from 3.022(2) to 3.027(3) Å). It is shown that preliminary irradiation with argon ions (dose of 10 22 m –2 , E = 20 keV) affects no surface damage of the central region, while in the adjacent heat-affected zone, there is a spallation of local surface regions.