Diffusion Resistance of Claddings for Corrosion Protection in Molten Salt Reactors

Abstract

The objective of the present study is to quantify the diffusion rates of Cr in corrosion-resistant claddings for use in molten fluoride salts. Diffusion couples of four candidate cladding and structural alloy combinations – stainless steel 316L and Incoloy 800H structural alloys, with Ni 200 and Hastelloy N claddings – were diffusion bonded at 900°C for two hours and thermally aged at 700°C for 1460 hours. Cr diffusion coefficients were calculated from EDS line scans. The results reported in this paper are a step towards predicting the durability of claddings in molten salt reactors (MSRs), and they allow comparisons of diffusion resistance to be made between four candidate cladding and structural alloy combinations.