Neutron irradiation impact on structural and electrical properties of polycrystalline Al2O3

Abstract

High energy neutron irradiations impact on structural and electrical properties of alumina are studied with particular emphasis on real time in-situ radiation induced conductivity measurement in low flux region. Polycrystalline Al2O3 samples are subjected to high energy neutrons produced from D-T neutron generator and Am–Be neutron source. 14 MeV neutrons from D-T generator are chosen to study the role of fast neutron irradiation in the structural modification of samples. Real time in-situ electrical measurement is performed to investigate the change in insulation resistance of Al2O3 due to radiation induced conductivity at low flux regime. During neutron irradiation, a significant transient decrease in insulation resistance is observed which recovers relative higher value just after neutron exposure is switched off. XRD results of 14 MeV neutron irradiated samples suggest annealing effect. Impact of relatively low energy neutrons on the structural properties is also studied using Am–Be neutrons. In this case, clustering is observed on the sample surface after prolonged neutron exposure. The structural characterizations of pristine and irradiated Al2O3 samples are performed using XRD, SEM, and EDX. The results from these characterizations are analysed and interpreted in the manuscript.

Keywords

• Al2O3
• Neutron irradiation
• Radiation induced conductivity
• Structural properties
• Annealing
• Defects