Thermal properties of beryllides as advanced neutron multipliers for DEMO fusion application

The hydrogen generation with steam is a major drawback of using beryllium (Be) as neutron multipliers in water-cooled blankets. Advanced neutron multipliers having considerable stability at high temperatures are desirable and beryllides depict a strong potential to be applied. Be12V pebbles were successfully fabricated directly using the rotating electrode method. Hydrogen generation ratio and heat of reaction due to the hydrogen generation reaction of Be12V was observed to be two orders of magnitude less than that of Be. Be12V exhibited good resistance to steam. By performing computer simulations at the loss of coolant accident (LOCA), thermal excursion was observed to be very sensitive to the initial temperature under Be pebble packed blanket conditions. However, better thermal stability was observed for the beryllide-steam reaction.