Steam-chemical reactivity studies for irradiated beryllium

This paper reports the results of an experimental study to determine the influence of neutron irradiation effects on the chemical reactivity of beryllium exposed to steam. The study entailed measurements of the following: (1) swelling of irradiated Be specimens annealed at temperatures ranging from 450 degrees C to 1200 degrees C, (2) hydrogen generation rates for unirradiated Be control specimens exposed to steam at temperatures from 450 degrees C to 1200 degrees C, and (3) hydrogen generation rates and tritium mobilization rates for irradiated Be exposed to steam at temperatures from 450 degrees C to 700 degrees C. For irradiated Be, swelling occurred at temperatures above 600 degrees C and it increased to about 56% for an anneal temperature of 1200 degrees C. Tritium and He-4 were released concurrently from specimens that were annealed at 800 degrees C and above. Steam-Be reactivity measurements for the control specimens were consistent with previous work at temperatures above 700 degrees C, and the new measurements extended the reactivity database down to 450 degrees C. Steam-reactivity measurements for irradiated Be were comparable to control specimens for 600 degrees C and below, but, they indicated a significant enhancement in the chemical reactivity at 700 degrees C.