Mahdieh Mokhtari Dorostkar, Farzad Isazadeh, Akbar Abdi Saray
Polymers are widely investigated for radiation shielding applications due to their low density, ease of processing, and ability to be modified with high-density fillers. In this study, polymethyl methacrylate (PMMA) was reinforced with equal weight fractions of tungsten oxide (WO 3 ) and bismuth oxide (Bi 2 O 3 ) to develop a lightweight gamma-ray shielding composite. The samples were fabricated using a solution casting method with different total filler concentrations, and their shielding performance was evaluated experimentally using Cs-137 and Am-241 gamma sources. Monte Carlo simulations using MCNP6 and Geant4 were performed to validate the experimental results. Increasing the filler concentration improved the attenuation capability of the composites, with the highest linear attenuation coefficients reaching 0.0855 cm⁻¹ at 662 keV and 2.109 cm⁻¹ at 59.5 keV for the highest filler loading. The simulation results showed good agreement with the experimental measurements, confirming the potential of fabricated composites as lightweight gamma radiation shielding materials.