Surface Morphology of Refractory Metals Submitted to a Single Laser Pulse

Abstract:

The work investigates refractory metals (bulk W, W produced via plasma spraying, W-1% La₂O₃ and Mo) of interest as plasma facing materials in future nuclear fusion reactors. They have been irradiated by a single Nd:YAG laser pulse to simulate the effects of transient thermal loads of high energy occurring in a tokamak under operative conditions and then examined by SEM observations. In all the materials the laser pulse induces a crater in the central area of laser spot surrounded by a ridge due to movement of molten metal while in a more external area a network of cracks is observed. Diameter and depth of the crater, ablated volume and morphological features of the surrounding area exhibit differences depending on the specific metal, its physical and microstructural characteristics which affect vaporization, melting and heat propagation from the irradiated spot.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 1526-1531
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.1526
• Online since: January 2021
• Authors: Pasquale Gaudio, Roberto Montanari, Ekaterina Pakhomova, Maria Richetta, Alessandra Varone*
• Keywords: Laser, Nuclear Fusion Reactors, Plasma Facing Materials, Refractory Metals, Surface Morphology

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