Elemental analysis of ceramic insulation materials by INAA

The in-core detectors used in nuclear reactors for neutron flux measurements are usually exposed to the high temperatures around 300°C. The detectors are shielded for thermal and electrical using insulation ceramic spacers and tapes respectively to enhance their durability. The identification of the isotopes produced in the irradiated ceramic insulation materials during reactor operation is important for health physics activities in any radiological surveillance checks and in turn to provide better radiation safety to the operational personnel. In this context, the elemental analysis of ceramic insulation materials using Instrumental Neutron Activation Analysis (INAA) technique was carried out. INAA technique is widely used in analysing the samples of various matrices using KAMINI research reactor in IGCAR. Around 50 and 100 mg of ceramic spacer powder and tape respectively were taken along with standard reference material (SRM) NIST 1633b coal fly ash. The prepared samples and standard were irradiated in pneumatic fast transfer system (PFTS) position of KAMINI reactor for 4 h at 20 kW. The irradiated samples were cooled for an overnight inside the reactor after its shutdown. INAA technique was found to be the suitable non-destructive technique for simultaneous determination of multi elements in the ceramic insulation materials which otherwise demands stringent quantitative dissolution protocols for conventional wet chemical analytical methods