Radiation damage and annealing in plutonium tetrafluoride

Journal Article · 03 August 2017 · Journal of Nuclear Materials

DOI: https://doi.org/10.1016/J.JNUCMAT.2017.08.005 · OSTI ID:1413469

McCoy, Kaylyn ^[1]; Casella, Amanda ^[1]; Sinkov, Sergey ^[1]; Sweet, Lucas ^[1]; McNamara, Bruce ^[1]; Delegard, Calvin  ^[1]; Jevremovic, Tatjana ^[1]

---

1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Univ. of Utah, Salt Lake City, UT (United States)

A sample of plutonium tetrafluoride that was separated prior to 1966 at the Hanford Site in Washington State was analyzed at the Pacific Northwest National Laboratory (PNNL) in 2015 and 2016. The plutonium tetrafluoride, as received, was an unusual color and considering the age of the plutonium, there were questions about the condition of the material. These questions had to be answered in order to determine the suitability of the material for future use or long-term storage. Therefore, thermogravimetric/differential thermal analysis and X-ray diffraction evaluations were conducted to determine the plutonium's crystal structure, oxide content, and moisture content; these analyses reported that the plutonium was predominately amorphous and tetrafluoride, with an oxide content near ten percent. Freshly fluorinated plutonium tetrafluoride is known to be monoclinic. And during the initial thermogravimetric/differential thermal analyses, it was discovered that an exothermic event occurred within the material near 414 °C. X-ray diffraction analyses were conducted on the annealed tetrafluoride. The X-ray diffraction analyses indicated that some degree of recrystallization occurred in conjunction with the 414 °C event. This commentary describes the series of thermogravimetric/differential thermal and X-ray diffraction analyses that were conducted as part of this investigation at PNNL.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC05-76RL01830
• OSTI ID: 1413469
• Journal Information: Journal of Nuclear Materials, Journal Name: Journal of Nuclear Materials Journal Issue: C Vol. 496; ISSN 0022-3115
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English