Radiation Shielding Simulation for Wollastonite-Based Chemically Bonded Phosphate Ceramics

Neutron and gamma attenuation on Wollastonite-based Chemically Bonded Phosphate Ceramics (Wo-CBPCs) is studied with Monte Carlo simulation (MonteCarlo N-Particle, MCNP). Wollastonite-based CBPC is a composite material with several crystalline (Wollastonite and brushite) and amorphous phases (silica and amorphous calcium phosphates). The effect of lead incorporated into the ceramic as a gamma shield has been examined across various gamma energies as well as neutron attenuation of the ceramic. Besides this simulation effort, neutron activation analysis was also performed experimentally at the Missouri University of Science and Technology Reactor (MSTR) to determine the activation by neutrons of the ceramic. In the past, it was found that the attenuation coefficient was substantially improved by the incorporation of Pb in the Wo-CBPC. The improvements at energies above 300 keV ranged from 32 to 193.8% 1. In the present simulation, we found that the addition of PbO increased the neutron attenuation by 180 to 400% and accurately predicted gamma attenuation values for photon energies above 1000 keV