1. Natalia Cherkashina, Belgorod State Technological University named after V.G. Shukhov, Russian Federation
In this paper the possibility of synthesis of radiation-protective composite on the basis of nanotube asbestos and lead tungstate embedded into a lead-borosilicate matrix is studied. The paper also presents the data on linear attenuation coefficient of γ-quanta in composites of different compositions got by the calculation and experimental ways. In order to synthesize the radiation-protective composites a lead-borosilicate matrix was used as a binder. The optimal matrix composition comprises about 78,5 % of lead oxide (II); 13,2 % – boron oxide; 4,2 % – silicon oxide; 3,1 % – oxide of zinc, 0,4 percent lead oxide (IV); 0,6% of cerium oxide.
As a filler we used nanotube asbestos, with lead tungstate PbWO4. The composite was made by mixing all original components. Before mixing the glass matrix was wet ground in a ball mill up to specific surface area of not less than 2•104 cm2/g. In order to achieve good homogenization of the components in the powder mixture to obtain a composite mixture of isobutanol was added.
The finished composite was obtained by hot pressing in a mold at a pressure of 80 MPa. The heating temperature was lower than 450 oC.
To determine the intervals of the optimal structure of the components various compositions of the composite materials were investigated.
To assess the radiation-protective properties of composite materials developed by studying the attenuation coefficient of materials in relation to γ-radiation. The linear attenuation coefficient - the main parameter for evaluating the protective characteristics of the materials.
It is shown that all the developed composites have good physical-mechanical characteristics and can be used as structural materials. On the basis of theoretical calculation we described the graphs of the γ-quanta linear attenuation coefficient depending on the emitted energy for all investigated composites. We founded high radiation-shielding properties of all the composites on the basis of theoretical and experimental data.