BASICS OF THE DEVELOPMENT OF LEAD-FREE MATERIALS FOR SHIELDING IONIZING AND NON-IONIZING ELECTROMAGNETIC RADIATION

Abstract

The current trends in the field of protection of the population and workers from the effects of ionizing and nonionizing electromagnetic radiation are the development of lead-free protective materials. Existing lead-free protective materials are expensive and unacceptable for mass use and for covering large surfaces. The possibility of shielding radiation with composite materials made of latex (matrix) and magnetite (filler) is considered. The expediency of this approach is due to the prevalence of latexes (including in the liquid state) and the high content of magnetite in iron ore concentrate (more than 80%), which is produced in large volumes by mining and processing plants. It has been shown theoretically that the mass attenuation coefficients of ironcontaining materials, at least for low-energy radiation, do not differ critically from those of lead. Tests were performed on a latexbased composite material with 60% magnetite content (by weight). The radiation source was a radioactive isotope of cobalt used in medical equipment. The results show that the shielding coefficients (multiples of radiation intensity reduction) for a composite thickness of 1-5 mm are 1.2-3.2; the corresponding figure for lead of the same thickness is 1.5-3.9. This result can be considered quite acceptable given the low cost and environmental friendliness of the composite. The advantage of the composite is the high efficiency of the material in the ranges of ultra-high, ultra-high, and extremely high frequencies of electromagnetic radiation. The presence of ferromagnetic properties in magnetite provides high shielding coefficients for alternating magnetic fields of industrial frequency and stationary magnetic fields of diagnostic equipment. The expediency of determining the possibility of using industrial wastewater treatment products (heavy metal compounds) as shielding fillers is shown. The possibility of degradation of the polymer matrix under the influence of ionizing radiation requires research.