Effect of Material Variables on the Irradiation Performance of Boron Carbide

Boron carbide pellets were fabricated with variations in material parameters. The pellets were irradiated in the Experimental Breeder Reactor II (EBR-II) to determine the effect of these variations on the performance. Helium release from the material and swelling of the pellets are the primary measures of performance. It was determined that material with a smaller grain size released more helium and swelled less. The pellets with boron-to-carbon ratios greater than 4 to 1 did not perform well. Iron additions improved the performance of the material while density variations had little effect.