About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Materials Science and Engineering of Materials in Nuclear Reactors
|
Presentation Title |
Plasticity of Zirconium Hydrides: an Edge and Screw Planar Discrete Dislocation Model |
Author(s) |
Luca Reali, Daniel S. Balint, Mark R. Wenman, Adrian P. Sutton |
On-Site Speaker (Planned) |
Luca Reali |
Abstract Scope |
Hydrides are a major concern for the safety of Zr-alloys. Usually considered as a brittle phase embedded in a ductile matrix, micro-hydrides can withstand significant plastic deformation without cracking.
Both screw and edge dislocations satisfy the criteria for slip transmission. Both cases are analysed using planar discrete dislocation plasticity (DDP). Key parameters are the strength of the interface and the internal friction. They control where dislocations accumulate, and therefore where cracks are likely to be initiated.
It is argued that, with increasing hydride thickness, the transformation strain leads to forest hardening and to very high internal dislocation densities. Furthermore, interfacial dislocations at the semi-coherent interface may promote the formation of glide dislocation pile-ups in front of the hydride. The two scenarios are explored varying the hydride thickness.
Novel aspects: the implementation of a screw 2D-DDP, and its combination with conventional edge 2D-DDP for a three-dimensional stress analysis. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |