JC259 & JC259Z-4 are a field-castable dry mix that provides excellent neutron shielding characteristics.
It is typically cast into closed containers and retains its hydrogen content even at elevated temperatures. JC259 contains 0.9% boron. For better thermal neutron attenuation JC259Z-4 contains 4% boron.
JC259 is mixed on-site with water and provides a hydrogen atom density that is roughly 6% greater than that of pure water.While the recommended temperature limit for JC259 is 150 °F (66 °C), it will retain about 80% of its hydrogen content up to 300 °F (140 °C).
JC259 can be poured in layers and each layer forms a solid bond with the one underneath.It requires approximately 56lbs. of JC259 dry mix to produce 1 ft³ of cast material.The material is typically provided in fibre barrels weighing 165lbs (net).
Features at a glance
Excellent neutron shielding with 0.9% to 4% boron additive
Field-castable into closed containers
Maintains 80% of its very high hydrogen content up to 300°F
Uses include, walls, back filling and roof slabs for cyclotron facilities
Sets up in about 30 minutes, requires only mixing with water