Structural, morphological, mechanical and electrochemical properties of 532 nm Nd:YAG laser-irradiated vanadium at high fluence

In this work, effects of laser irradiation on several characteristics of vanadium (99.999%) are examined. The square-shaped vanadium samples were irradiated using pulsed Nd:YAG laser (532 nm, 6 ns) at a high fluence (7.46 J/cm 2 ) with 100, 200, 300, and 400 laser shots under vacuum. X-ray diffraction results revealed the preferred orientation of the unirradiated vanadium along (200) plane that remained un-changed upon laser irradiation. The crystallite size varied in the range 30–62 nm and the average diameter of laser-ablated region was decreased with the increase of laser shots. On the contrary, the heat-affected area around the ablated region and the surface roughness progressively increased on increasing the number of laser shots. The morphological features of the laser-irradiated vanadium comprised of cavities, microcones, cracks, grooves dips, bubbles, droplets, ripples, micro-pillars, and wave-like structures. The hardness of the samples (166–184 HV) was decreased with increase of the crystallite size (30–62 nm) and vice versa. The samples irradiated with the laser for 100 and 200 shots exhibited a higher corrosion rate as compared to the un-irradiated sample. However, the corrosion rate was reduced as the number of laser shots were increased to 300 and then 400, demonstrating an improvement in the vanadium corrosion resistance.