Speaker
Jae-Hwan Kim
(Department of Blanket Systems Research)
Description
As a water-cooled solid breeder blanket of a fusion reactor, safety concern has become one of the most critical issues. In specific, Be pebbles as a multiplier have been well-known to generate hydrogen and exothermally react while reacted with water vapor at high temperature. In contrary to these Be pebbles, Beryllium intermetallic compounds (beryllides) are one of promising materials because of its much more stable chemical reactivity.
Work on the development of advanced neutron multipliers by Japan and the EU is part of the DEMO R&D activities at the International Fusion Energy Research Center (IFERC) project, which forms a part of the Broader Approach (BA) program. Fabrication methods of beryllides pebbles have been successfully developed by combining a plasma sintering synthesis method and a rotating electrode granulation method.
From the results of pebbles fabrication, as-received Be12Ti pebbles which consisted of Be, Be12Ti and Be17Ti2 phases, homogenized Be12Ti pebbles, and as-received Be17Ti2 pebbles have been successfully fabricated. Using these pebbles with a reference of Be pebbles, oxidation property, hydrogen generation, and reaction heat were investigated.
Beryllides pebbles indicated much more resistant to oxidation by H2O, lower hydrogen generation and reaction heat than Be pebble. Among these beryllides pebbles, homogenized Be12Ti pebbles and as-received Be17Ti2 pebbles showed lower weight gain, hydrogen generation and reaction heat than as-received Be12Ti because as-received Be12Ti pebbles contains some fractions of Be phase inside pebbles.
Co-authors
Jae-Hwan Kim
(Department of Blanket Systems Research,, Japan Atomic Energy Agency, Rokkasho, Kamikita,, Japan)
Masaru Nakamichi
(Department of Blanket Systems Research,, Japan Atomic Energy Agency, Rokkasho, Kamikita,, Japan)
