Assessment of Mechanical Property of Ti-5Ta-2Nb and 304L SS Explosive Clad and Correlation with Microstructure

AbstractSpent fuel reprocessing plants of FBRs require advanced structural materials for service in aggressive conditions. Ti-5Ta-2Nb is a candidate structural material for electrolytic dissolver whereas 304L SS is used for rest of the plant. ‘Zero failure’ requirement for the process vessels necessitated the development of defect free explosive clad between Ti-5Ta-2Nb and 304L SS. The paper deals with the investigations carried out on the mechanical properties and microstructure of the explosive clads, and modification in microstructure on subsequent thermal exposure. The structural integrity of the clad as a consequence of these structure-property changes is also discussed in the paper

Simulation of nitrogen diffusion in Ni vis-à-vis Fe – Identification of better structural material for neutron detectors

Inconel 600, a Ni-based alloy was considered as a possible replacement for austenitic stainless steels for service at high temperatures in nitrogen containing atmosphere of the neutron detector. To obtain a fundamental understanding of the differences in the diffusivity of nitrogen in pure Fe and Ni lattices, molecular dynamics simulations were carried out. Based on the simulation of nitrogen trajectories in the temperature range of 1200–1400 K, pre-exponential factor, activation energy and jumping frequency were calculated and compared for fcc Ni and Fe. MD simulations confirmed that rate of diffusion of nitrogen is lower in Ni when compared to Fe, suggesting the replacement of austenitic steel with Inconel 600 for better performance of the detectors