Fabrication and characterization of large size 6LiF/CaF2:Eu eutectic composites with the ordered lamellar structure

As alternative candidates for the 3He neutron detectors, 6LiF/CaF2:Eu eutectic composites were fabricated and their scintillation properties were evaluated. Large size LiF/CaF2:Eu eutectic composites of 58 mm diameter and 50 mm thickness were produced by Bridgman method. The composites had a finely ordered lamellar structure along the solidification direction. The lamellar structure was controlled by the direction and the rate of solidification, and it was optimized to improve the scintillation properties. Better results were achieved when thinner lamellar layers were aligned along the scintillation light path.