Abstract
The thermal expansion coefficient of δ hydrides and the evolution of the d-spacing of δ hydride platelets in Zircaloy-4 during heat treatments were investigated by conducting synchrotron x-ray diffraction experiments. Identical experiments enabled a direct comparison of the d-spacing of δ zirconium hydride platelets with the d-spacing of the powder δ hydrides. By analyzing the experimental data of this study and the data available in the literature, the thermal expansion coefficient of pure δ hydrides was determined as 14.1 10−6 °C−1. A direct comparison of the d-spacings of δ hydride platelets in CWSR Zry-4 sheet and the powder δ hydride samples showed an evolution of temperature-dependent strains within the δ hydride precipitates in which the strain components normal to the platelet edges exceed that normal to the platelet face during cooling/precipitation but not during heating/dissolution above approx. 200 °C.
| Original language | English |
|---|---|
| Pages (from-to) | 566-576 |
| Number of pages | 11 |
| Journal | Journal of Nuclear Materials |
| Volume | 509 |
| DOIs | |
| State | Published - Oct 2018 |
Funding
This material is based upon work supported by the U.S. Departmeny of Energy , Office of Nuclear Energy funded Nuclear Energy University Program Integrated Research Project 17-13708 . Authors thank Peter Mouche, Rachel Seibert for their assitance on the powder sample characterizations. Authors thank Douglas Robinson from APS/ANL for his assistance during experiments. Authors acknowledge Donald Koss for the fruitful discussions.
Keywords
- Dissolution and precipitation
- Lattice parameter
- Mechanical strain
- Synchrotron radiation
- Thermal expansion coefficient
- Zirconium hydrides
- δ hydrides