Preparation of pollucite ceramic matrices as 137Cs ionizing radiation source by spark plasma sintering

Abstract

The paper proposes an original one-stage method using spark plasma sintering technology (SPS) of manufacturing the ionizing radiation source (IRS) of closed type with a non-dispersible ceramic core based on pollucite obtained using aluminosilicate raw materials saturated (24.3 wt%) with cesium, and doped with 10–40 wt% CsCl. According to the XRD, EDX, AAS and DTA-TG data, optimal conditions for hydrothermal synthesis zeolite NaA were established, the consolidation kinetics and phase transformations into ceramic pollucite under SPS conditions were studied. The ceramics had a relative density of 99.8 % and mechanical strength up to 732 MPa, a low rate of cesium leaching 10−7 g/cm2 day and thermal resistance in air up to 1000 °C. It was confirmed by SEM and EDX that the destruction and deformation of pollucite ceramics in the composition with CsCl and steel at the boundary of their contact in the design of the IRS product was absent and diffusion of cesium outside the ceramics did not occur. The achieved cesium content in the ceramic core of the resulting the ionizing radiation source, which meets high quality and regulatory requirements, is 44.3 wt%. The results of the study may be promising for the manufacture of industrial products.