Radiation attenuation properties of spark plasma sintered boron carbide-zirconium diboride composites against diagnostic x-rays

This study focused on the x-ray radiation attenuation properties of spark plasma sintered boron carbide-zirconium diboride (B₄C-ZrB₂) composites against diagnostic x-rays. The ZrB₂ amount ranged from 0 to 15 vol%. Diagnostic x-rays were applied using the tube voltages ranging from 50 to 110 kV in 10 kV increments. The linear and mass attenuation coefficients, as well as the Half-Value Layers (HVLs) and Tenth-Value Layers (TVLs), were determined for all applied tube voltages. Fast neutron removal cross sections (FNRCSs) were also figured out for studied B₄C-ZrB₂ composites. It has been revealed that the addition of ZrB₂ to B₄C enhanced not only the x-ray attenuation capability across all applied tube voltages but also increased FNRCS values. In addition, Radiation attenuation ratios (RARs) and lead equivalent thickness (PbE) values were calculated for all samples. Increasing the amount of ZrB₂ in the samples caused higher radiation attenuation coefficients. While one cm thick monolithic B₄C had an average PbE of 0.019 mm, one cm thick B₄C- %15 ZrB₂ had an average PbE of 0.404 mm, which indicates that BZ15 demonstrated approximately 25 times better radiation attenuation performance than monolithic B₄C. In addition, a 1 cm thick BZ15 composite provides at least 0.35 mm PbE radiation shielding performance for the studied diagnostic x-rays, which is equivalent to approximately 17.5% of the 2 mm Pb sheets typically used in x-ray protection applications. These findings have the potential to minimize Pb usage, thereby supporting sustainable alternatives. In conclusion, ZrB₂-added B₄C materials exhibit superior radiation attenuation properties compared to monolithic B₄C.