About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Materials and Chemistry for Molten Salt Systems
|
Presentation Title |
Understanding the Mechanisms of Corrosion in 316 Stainless Steels and Advanced Ni-based Alloys in Molten FLiNaK at 700oC |
Author(s) |
William Doniger, Govindarajan Muralidharan, Adrien Couet, Kumar Sridharan |
On-Site Speaker (Planned) |
Kumar Sridharan |
Abstract Scope |
The corrosion behavior of 316H and 316L stainless steels and computationally designed advanced Ni-based alloys with creep strength superior to Hastelloy-N has been investigated in FLiNaK at 700oC. The higher degree of sensitization in 316H compared to 316L on account of higher carbon content was beneficial for corrosion resistance. In both types of stainless steels, surface recession and preferential grain boundary attack were observed. For the Ni-based alloys surface recession was minimal and corrosion and depletion of alloying elements occurred from within the grains, and weight loss was notably lower than for the stainless steels. Analysis of salt composition before and after corrosion tests, microstructural and compositional analysis of corrosion effected near-surface region, and weight change measurements provided a comprehensive understanding of corrosion mechanisms in these candidate structural alloys. Electrochemical polarization tests provided a scientific basis for understanding the mechanisms for preferential grain boundary attack versus uniform grain corrosion. |
Proceedings Inclusion? |
Planned: |
Keywords |
Nuclear Materials, Environmental Effects, High-Temperature Materials |