Damage studies on tungsten due to helium ion irradiation

Surface modifications of fusion reactor relevant materials on exposure to fusion grade plasma in plasma focus device

“…The SEM micrographs of the W sample surface before and after irradiations are shown in Fig. 2 [21] and with helium ion [35] in the PF device. These materials have indicated "brittle fracture" tendencies under pulse irradiations.…”

Tuning surface porosity on vanadium surface by low energy He+ ion irradiation

“…Surface cracks in some applications, including plasma-facing materials for nuclear fusion, are not preferred and could deteriorate the material's performance and lifetime. Recently, Xu et al [65] (using high-flux deuterium plasma) and Dutta et al [66] (using helium ion pulse) have shown evidence of similar surface cracking in W. While the surface cracking in W studied by Dutta et al [66] is relatively close to cracks observed in V, the ion irradiation conditions are different. The formation mechanism of such surface cracks may understood as follows: growth-induced interstitials and/or defects such as GBs, dislocations, and vacancies are almost always present in the cast refractory V as a second phase and may contribute to the appearance of cracks at GBs since they are considered to be the main regions for He dissolution and accumulation [67].…”

Especies ligeras en materiales de interés para aplicaciones energéticas

“…Actualmente, el wolframio (W) es considerado como una de las alternativas más robustas para cumplir la función de PFM, debido a su elevado punto de fusión (3695 K) y su conductividad térmica (aproximadamente 160 W m -1 K -1 ), bajo coeficiente de sputtering y baja retención de tritio [12,14,[26][27][28][29]. Sin embargo, las condiciones de operación (típicamente, de flujos de partículas superiores a 10 19 cm -2 s -1 ) suponen todo un reto para la aplicación de este material, tanto por consideraciones termomecánicas [30] como atomísticas, siendo estas últimas de mayor relevancia al ser responsables de una miríada de efectos perjudiciales, como agrietamiento, hinchamiento, exfoliación, y, bajo ciertas condiciones, el crecimiento de nanoestructuras superficiales de baja densidad conocidas globalmente como "fuzz" [31][32][33][34][35][36].…”