Sputter-deposition of metastable Ta--Pu and Co--Pu alloys

Conference · Tue Jan 01 00:00:00 EST 1974

OSTI ID:4172410

Allen, R P; Dahlgren, S D; Wang, R

High-rate sputter-deposition techniques were used to prepare supersaturated solid solution alloys for the normally immiscible Ta--Pu and Ag-- Pu systems and to investigate the effect of substituting Pu for the rare-earth element in sputtered amorphous Co--Sm alloys. Two Ta--8 at. percent Pu deposits were prepared, which exhibited a unique two-phase bcc $alpha$-Ta and tetragonal $beta$-Ta structure. Both phases formed a metastable solid solution with the Pu resulting in an 0.85 percent increase in the $alpha$-Ta(a) parameter and a 1.5 percent increase in the $beta$-Ta(c) parameter. The metastable $beta$-Ta solid solution decomposed at a significantly lower temperature (less than 825$sup 0$K) than the $alpha$-Ta solid solution (975$sup 0$K). A Ag--0.5 at. percent Pu solid solution was obtained by co-sputtering the elements onto a liquid nitrogen cooled substrate. The solid solution was retained to room temperature for x-ray diffraction studies. The lattice parameter of the Ag was expanded from 4.086 A to 4.091 A, representing a positive deviation from Vegard's law. A Co--11 at. percent Pu alloy (Pu$sub 2$Co$sub 17$) was sputter-deposited at 290$sup 0$K for comparison with sputtered amorphous Sm$sub 2$Co$sub 17$. Both alloys formed a CaCu$sub 5$-type structure on annealing, with subsequent transformation to the equilibrium Th$sub 2$Zn$sub 17$ (Co--Sm) and Th$sub 2$Ni$sub 17$ (Co--Pu) structures. The deposition and annealing results indicate that the sputtered Co-- Pu alloy has a microcrystalline structure. Results suggest that amorphous plutonium alloys equivalent to the sputtered amorphous rare-earth-transition metal series can be obtained by sputter-depositing plutonium-transition metal alloys with a higher Pu content. (auth)

• Research Organization: Battelle Pacific Northwest Labs., Richland, Wash. (USA)
• DOE Contract Number: AT(45-1)-1830
• NSA Number: NSA-33-001198
• OSTI ID: 4172410
• Report Number(s): BNWL-SA-5325; CONF-750915-18
• Resource Relation: Conference: 5. international conference on plutonium and other actinides, Baden-Baden, F.R. Germany, 10 Sep 1975; Other Information: Orig. Receipt Date: 30-JUN-76
• Country of Publication: United States
• Language: English

Related Subjects

N50220* -Metals
Ceramics
& Other Materials-Metals & Alloys-Preparation & Fabrication
N50230 -Metals
Ceramics
& Other Materials-Metals & Alloys-Properties
Structure & Phase Studies
360101* -Materials-Metals & Alloys-Preparation & Fabrication
*PLUTONIUM ALLOYS- SPUTTERING
AMORPHOUS STATE
ANNEALING
BINARY ALLOY SYSTEMS
COBALT ALLOYS
COPPER
SUBSTRATES SILVER ALLOYS
TANTALUM ALLOYS