La distribution on the crater surface of W-1%La2O3 produced by a single laser pulse |
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Authors: | Saulius Kaciulis Alessio Mezzi Roberto Montanari Maria Richetta Ekaterina Pakhomova Alessandra Varone |
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Institution: | 1. Institute for the Study of Nanostructured Materials (ISMN), CNR, Rome, Italy;2. Department of Industrial Engineering, University of Rome “Tor Vergata”, Rome, Italy |
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Abstract: | The W-1%La2O3 alloy has been irradiated by a single laser pulse (λ = 1064 nm) to simulate transient thermal loads of high energy occurring in a tokamak under operative conditions. A zone with a diameter of ~2 mm, namely, much larger than the focal spot, results to be affected by the pulse, and a crater of about 300 μm is observed in its center. La2O3 particles are not present inside the crater. The change of surface morphology is accompanied by elemental redistribution. Multipoint XPS analysis evidenced that the concentration of La is very low in the crater and increases moving toward the border of the affected zone while that of W shows an opposite trend. The composition changes involve only the outmost 5 nm of the sample: through depth profiling, no differences of chemical composition were detected deeper in the alloy between the center and external border of the affected area. |
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Keywords: | laser microstructure nuclear fusion reactor W-La2O3 XPS |
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