| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Emergent Materials under Extremes and Decisive In Situ Characterizations
|
| Presentation Title |
Multi-Scale Investigation of Heterogeneous Swift Heavy Ion Tracks in Pyrochlore Oxides |
| Author(s) |
Eric O'Quinn, Cameron Tracy, William Cureton, Ritesh Sachan, Joerg Neuefeind, Christina Trautmann, Maik Lang |
| On-Site Speaker (Planned) |
Eric O'Quinn |
| Abstract Scope |
Pyrochlore oxides (A2B2O7) form a large family of phases with a variety of properties attractive for technologies operating in extreme conditions (e.g., intense radiation). We irradiated pyrochlores with swift heavy ions (2.2 GeV) and characterized the structural modifications with electron microscopy (TEM) and X-ray diffraction (XRD). Further, the large penetration depth of such energetic ions enabled neutron scattering with pair distribution function (PDF) analysis. TEM and XRD revealed a track structure with an amorphous core surrounded by a disordered fluorite shell. Neutron total scattering, with sensitivity to oxygen, also revealed a crystalline but defective pyrochlore phase distinct from the pristine pyrochlore matrix. This phase forms a halo beyond the core–shell morphology evidenced by TEM. All phases (amorphous, disordered, and defective pyrochlore) can be modeled with a weberite-type configuration, characteristic of A3BO7 oxides. Finally, the ion-induced evolution of material phases across all-length scales was used to improve existing track-overlap models. |