Fabrication and Characterization of Tungsten and Bismuith Nano Structured Protective Shields against X-rays

Abstract

Interest have been shown in finding novel, effective and highly safe radiation shielding materials to replace the commonly used radiation shielding materials like lead that are heavy, toxic and environmentally hazardous. In this study, W and Bi nano structured protective shields were fabricated and characterized for use against X-rays. WO₃ and Bi₂O₃ nano powders with particle size 0.4 µm were used and the PVC powder and DOP oil were used as softeners for shields. Two sets of sample shields made of tungsten and bismuth were formed with thicknesses 1.5, 2.0 and 2.5 ± 0.4 mm, respectively. The sample shields were exposed to X-rays with X-ray tube voltages of 40, 50, and 60 kVp, for all the thicknesses. The half value layers and the attenuation coefficients of the shielding materials at varying thicknesses were determined. At 40 and 50 kVp X-rays exposures, Bi indicate higher attenuation properties than W, whereas at 60 kVp, both protective shields showed similar effect. At 50 and 60 kVp X-rays exposures, Bi showed a higher attenuation coefficients as compared to W for all the various thicknesses of the shield used. The findings showed that the nano-structured samples have attenuating abilities and that Bi attenuating ability at 60 kVp is closer to lead than W, this shows that these nano-structured materials have potentials to replace lead.