Formation of Pu amorphous alloys or metastable structures in Pu-Fe, Pu-Ta, and Pu-Si alloys
Sputter deposition technique was used to study the possible formation of amorphous structures in Pu-Fe, Pu-Ta, and Pu-Si systems. A triode sputtering system was used to prepare sputtered coatings: 13 to 59 at. % (a/o) Fe, 10 to 50 a/o Si, and 15 to 65 a/o Ta. Structure of the coatings was determined by x-ray diffraction techniques. The temperature stability of the obtained structures was determined by Differential Scanning Calorimetry (DSC) measurements. The Pu-Fe and Pu-Si binary systems showed strong evidence for the formation of amorphous phases in the sputtered coatings. X-ray analyses indicated the presence of Pu6Fe in the 13 to 20 a/o Fe range of Pu-Fe alloys and no apparent crystalline phases over the entire 10 to 50 a/o Si range of Pu-Si alloys. In the Pu-Ta system, the DSC data obtained for compositions below 50 a/o Ta did not show typical crystallization exotherms. At compositions above 50 a/o Ta, a metastable bcc alpha Ta structure was observed with an expanded lattice parameter. The calculated volume expansion (2.9%) corresponds to 29 a/o of Pu in solid solution if the lattice parameter is assumed to follow Vegards Law. After storage in a nitrogen glovebox atmosphere for over two years, the Pu-Si and Pu-Ta coatings have maintained a metallic luster and have shown no visible evidence of surface oxidation.
- Research Organization:
- Lawrence Livermore National Lab., CA (USA)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 6129914
- Report Number(s):
- UCRL-92693; CONF-8509147-14; ON: DE86005809
- Resource Relation:
- Conference: ACTINIDES '85, Aix-en-Provence, France, 1 Sep 1985
- Country of Publication:
- United States
- Language:
- English
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