NSUF 19-1732: Radiation Tolerance of Nanoporous Gadolinium Titanate
The method that will be employed to study the radiation tolerance of the pyrocholore sample (nanoporous gadolinium titanate) is in-situ ion irradiation with in the transmission electron microscopy. This study is enhanced by our sample’s unique microstructure. The sample has three different layers that have different microstructural features: nanograined, nanoporous, and single crystal. Where this study advances on the literature is by introducing the concept of the nanopores as an alternative to other microstructurs with a high density of defect sink. The surface of such pores are expected to act as more efficient/effective defect sinks in comparison to the dense nanograined samples. This unique microstructure has the promise of improving the suitability of pyrocholore ceramic systems for nuclear waste forms. There are many studies that focus on the microstructure-amorphization relationship, but none of them consider a nanoporous structure. Most studies consider a single microstructural characteristic e.g. just single crystal or nanograined. Because our specimen contains three unique microstructural configurations, the in-situ observations will allow us to directly compare the irradiation behavior of the pyrochlore systems under the exact same irradiation conditions. Four different temperature regimes will be explored wherein we will target unique regimes of defects mobilities and recombination rates according to current understanding of radiation enhanced diffusion. The data that will be collected during these experiments include both video and selected area electron diffraction patterns. The in-situ video collected during irradiation can be post-processed to provide detailed information on the microstructural changes, e.g. pore coarsening or grain growth, in the sample as function of irradiation dose. This is an important aspect of the experiment because microstructure changes will affect the effectiveness of the defect sinks, e.g. by increasing the distance between sinks, with in the microstructure. The selected area electron diffraction patterns for each of the unique microstructural configurations will be collected after a set dose. These images will indicate the progress towards amorphization (degree of crystallinity) in each of the areas. These observations have the potential to impact the state of the knowledge base in the nuclear ceramics and fuels communities by showing a new microstructures that can enhance the radiation tolerance of the pyrochlore systems. This enhanced radiation tolerance of the pyrochlore class of ceramics will make the nuclear waste disposal material a stronger candidate.
Additional Info
| Field | Value |
|---|---|
| Abstract | The method that will be employed to study the radiation tolerance of the pyrocholore sample (nanoporous gadolinium titanate) is in-situ ion irradiation with in the transmission electron microscopy. This study is enhanced by our sample’s unique microstructure. The sample has three different layers that have different microstructural features: nanograined, nanoporous, and single crystal. Where this study advances on the literature is by introducing the concept of the nanopores as an alternative to other microstructurs with a high density of defect sink. The surface of such pores are expected to act as more efficient/effective defect sinks in comparison to the dense nanograined samples. This unique microstructure has the promise of improving the suitability of pyrocholore ceramic systems for nuclear waste forms. There are many studies that focus on the microstructure-amorphization relationship, but none of them consider a nanoporous structure. Most studies consider a single microstructural characteristic e.g. just single crystal or nanograined. Because our specimen contains three unique microstructural configurations, the in-situ observations will allow us to directly compare the irradiation behavior of the pyrochlore systems under the exact same irradiation conditions. Four different temperature regimes will be explored wherein we will target unique regimes of defects mobilities and recombination rates according to current understanding of radiation enhanced diffusion. The data that will be collected during these experiments include both video and selected area electron diffraction patterns. The in-situ video collected during irradiation can be post-processed to provide detailed information on the microstructural changes, e.g. pore coarsening or grain growth, in the sample as function of irradiation dose. This is an important aspect of the experiment because microstructure changes will affect the effectiveness of the defect sinks, e.g. by increasing the distance between sinks, with in the microstructure. The selected area electron diffraction patterns for each of the unique microstructural configurations will be collected after a set dose. These images will indicate the progress towards amorphization (degree of crystallinity) in each of the areas. These observations have the potential to impact the state of the knowledge base in the nuclear ceramics and fuels communities by showing a new microstructures that can enhance the radiation tolerance of the pyrochlore systems. This enhanced radiation tolerance of the pyrochlore class of ceramics will make the nuclear waste disposal material a stronger candidate. |
| Award Announced Date | 2019-05-14T15:54:56.767 |
| Awarded Institution | Center for Advanced Energy Studies |
| Facility | Microscopy and Characterization Suite |
| Facility Tech Lead | Wei-Ying Chen, Yaqiao Wu |
| Irradiation Facility | Intermediate Voltage Electron Microscopy (IVEM)-Tandem Facility |
| PI | Jessica Krogstad |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 1732 |