Document Type : Research Paper

Author

• mir mohammad reza seyedhabashi

Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute (NSTRI), Atomic Energy Organisation of Iran (AEOI), P.O. Box: 14399-51113, Tehran, Iran

Abstract

In this research, the effects of high-energy proton bombardment produced by the plasma focus device on the surface morphology and structural parameters of tungsten and molybdenum were investigated. Tungsten and molybdenum samples, placed at a distance of 6 cm from the anode head, were irradiated with hydrogen ions in 20 discharges. The samples were examined before and after irradiation using a scanning electron microscope (SEM). The SEM results revealed the formation of blisters, cracks, and surface melting on both tungsten and molybdenum samples due to the high-energy proton irradiation. To characterize the ion beam of the plasma focus device, Lee's code was employed. The results from Lee's code indicated that approximately 7.9 × 1014 ions are emitted from the plasma column in each discharge. Additionally, the SRIM code was utilized to calculate the damage created in tungsten and molybdenum, as well as the hydrogen density at various depths within the materials. According to the SRIM code results, the maximum value of displacements per atom (dpa) per shot for tungsten and molybdenum samples irradiated with hydrogen ions was estimated to be 0.025 and 0.014, respectively, at depths of 150 nm and 250 nm. Moreover, the maximum concentration of hydrogen ions in the irradiated samples of tungsten and molybdenum at depths of 150 nm and 250 nm was found to be 0.4% and 0.035%, respectively.

Keywords

• plasma focus device
• plasma facing material
• tungsten
• molybdenum
• radiation damage

Main Subjects

• PLASMA PHYSICS AND FUSION THECHNOLOGY