[2L13-17] Structural Materials for Nuclear Fusion Reactors 2

[2L13] Multiple irradiation experiment of tungsten materials by negative hydrogen ion beamⅡ

(1) Surface damage of multiple irradiated tungsten

*Makoto Fukuda¹, Kazutoshi Tokunaga², Koichiro Ezato¹, Koichiro Hirano³ (1. National Institutes for Quantum Science and Technology, 2. KYUSHU UNIVERSITY, 3. Japan Atomic Energy Agency)

Keywords:Tungsten, Heat load test, Surface damage, ITER divertor

Tungsten which is used as a plasma-facing material of the ITER divertor, is expected to receive various type of heat load during ITER operation. Therefore, it is necessary to understand the surface damage of tungsten under various heat load conditions. In this study, as part of the investigation of the effects of short-pulse repetitive heat loads on tungsten, the effects of multiple irradiations of the negative hydrogen ion beam (3 MeV, 5 Hz) on the surface of tungsten were investigated. As a result of the investigation, it was clarified that microcracks were formed on the surface of tungsten exposed to multiple irradiations, and that the microstructure was also changed.