Present status of beryllide R&D as neutron multiplier

Present status of beryllides for fusion and industrial applications in Japan

“…It is obvious that the reaction layer thickness for three alloys is almost the same and very small. Note that both Be-5 at.%Ti and Be-7 at.%Ti include (Be) phase in Be 12 Ti, while Be-8.5 at.%Ti consists of only beryllide phases of Be 12 Ti and Be 10 Ti according to the Be-Ti binary phase diagram recently evaluated [1]. Though it is known that the existence of (Be) phase degrades the compatibility, no degradation was found at 873 K, which is the typical operation temperature in DEMO fusion blanket.…”

“…Characterizations concerning the compatibility with structural material and ceramic breeder, oxidation, steam reaction, tritium inventory, irradiation effects in Japan materials testing reactor (JMTR) and the structural evolution induced by charged particle irradiation have been carried out and the advantages were made clear. These results are summarized in a review paper by Kawamura et al [1].…”

“…In order to impart some room temperature ductility to intrinsically brittle Be 12 X type intermetallic compounds, two-phase alloys involving Be solid solution, hereafter (Be), are prepared in Be-Ti and Be-V systems and the relationships between microstructure and mechanical properties are examined based on the recently assessed phase diagrams of both systems [1]. In both alloy systems, Ti or V concentration is preliminary chosen as 3 and 5 at.% and the microstructures are observed for as-cast condition as well as for hot-rolled conditions by 25 and 50% reductions.…”

Overview of research and development activities on fusion nuclear technologies in Japan

“…As for neutron multiplier materials, recent R&D has been focused on Be alloys, in particular Be-Ti alloys as an advanced option, because of better properties, such as compatibility with structural materials and oxidation resistance at higher temperatures [12]. Basic characterization using HIPped Be 12 Ti has also been performed.…”

General properties on compatibility between Be–Ti alloy and SS 316LN

“…Therefore, it is necessary to develop an advanced material for the neutron multiplier that has high temperature resistance and high radiation resistance. Beryllium alloys such as Be-Ti and Be-V have been expected to be promising candidates for advanced neutron multipliers for their high melting point, high 0920 [3,4].…”