About this Abstract |
Meeting |
Materials in Nuclear Energy Systems (MiNES) 2021
|
Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2021
|
Presentation Title |
The Effect of Phase Structure on the Aqueous Corrosion of Yttrium Disilicate |
Author(s) |
Keith C. Bryce, Kun Yang, Jie Lian |
On-Site Speaker (Planned) |
Keith C. Bryce |
Abstract Scope |
In deep geological repositories, rare earth elements may react with silicates found in the surrounding engineered barrier systems to form rare earth disilicates (RE2Si2O7). This study investigates the chemical durability of Y2Si2O7 polymorphs with different phases (amorphous, alpha, beta, and gamma) in dense sintered pellets by semi-dynamic leaching tests. The gamma phase showed the lowest leaching rates for both Y and Si, followed by beta, alpha and the amorphous pellet, suggesting a strong impact of phases on chemical durability of disilicates. Incongruent leaching was observed for all phases with a preferential release of Y from the matrix. Microstructural analysis of the post leaching sample revealed variations in the level of corrosion of the surface grains for the beta and gamma pellets. |
Proceedings Inclusion? |
Undecided |