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Beryllium intermetallic compounds (beryllides) such as Be12Ti and Be12V are the most promising advanced neutron multipliers in demonstration (DEMO) power reactors because of their low swelling and high stability at high temperatures. In this work, beryllides pebbles with binary and ternary compositions were successfully fabricated by combining plasma sintering and rotating electrode methods. After 3 keV D2+ ions were implanted to the beryllides pebbles, the deuterium desorption and retention properties were investigated by thermal desorption spectroscopy to investigate hydrogen desorption and retention of these materials for fusion application. The desorption properties and retention of hydrogen isotopes (deuterium) using the newly developed beryllide pebbles indicated that the beryllide pebbles exhibited better deuterium desorption properties, such as lower starting-up temperature, total retention, and activation energy for deuterium desorption than beryllium.

Beryllium intermetallic compounds (beryllides) are known as promising materials for advanced neutron multipliers for fusion applications owing to their high stability and low swelling. Because a large amount of beryllium is used for each solid breeding blanket in fusion reactors, the development of effective and efficient recycling processes is essential. In this study, a proper recycling process of Be12V pebbles was proposed, which combines a plasma sintering and a rotating electrode method for the fabrication of beryllide pebbles. As a result of experiments, it is determined that the rotating electrode method is available to reduce oxygen impurities, whereas the plasma sintering process can eliminate Li impurities and hydrogen isotope depending on sintering temperature. Regarding the recycling process, the beryllide pebbles used can be recycled into rods by plasma sintering, in which Li impurity and tritium can be eliminated. Then, recycled rods can be granulated by the rotating electrode method. During this process, it is anticipated that oxygen impurities and irradiation defects can be eliminated because the rotating electrode method includes the melting process. Thus, the current process was determined to be appropriate as a recycling process for beryllide pebbles.

A demonstration (DEMO) fusion reactor will require a huge amount of beryllium (Be) with approximately 490 tons. Since the total production of Be in the world, for now, is approximately 300 tons per year, it is anticipated that the demand is dramatically increased as the early realization of the fusion reactor proceeds. The presence of many Be mines, as well as information on each Be reserve, has already been confirmed with surveys. Since a conventional Be refinement process is considerably complicated including a production process for an intermediate product, Be(OH)2, high-temperature treatments, and handling of toxic powdery states, however, Be raw materials are costly. To provide a steady supply of Be for DEMO, in parallel with the development of mines, a novel Be refinement technique using an economical and safe process is imperative. According to these requirements, a novel and advanced refinement process of Be metal from ores was suggested by applying microwave melting at low temperatures through wet processing. It was obvious as a result of dissolubility tests that bertrandite and beryl ores were completely dissolved by using a process with acid solutions and microwave heating after treatment with base solutions and microwave heating. Further, the process can be utilized to produce not only intermediate products, such as beryllium hydroxide (Be(OH)2) and beryllium oxide (BeO) but also pure beryllium metal. Moreover, this process has great advantages for extracting uranium which is one of critical issues and oxide impurities for reuse.