Phase stability in Be-Nb and Be-Nb-Zr intermetallics

Conference · Sun Sep 01 04:00:00 EDT 1991

OSTI ID:5061121

Brimhall, J L; Charlot, L A; Bruemmer, S M

Sputter deposition of Be-Nb alloys at low temperature (30{degrees}C) produces an amorphous phase for compositions >5 at.% Nb. A metastable crystalline phase which can be considered a highly faulted form of the Be{sub 12}Nb occurs at higher deposition temperatures or by low-temperature annealing of the amorphous phase. Because of structural similarities, this metastable phase is a precursor to the formation of either Be{sub 12}Nb or Be{sub 17}Nb{sub 2} upon high temperature annealing. There was no evidence of the Be{sub 5}Nb phase which has been postulated on some phase diagrams. The Be{sub 12}Nb phase can accomodate considerable Zr in the structure and the Be{sub 13}Zr can accomodate Nb into its structure. The Be{sub 13}Zr becomes the predominant phase when the Zr/Nb composition ratio > 1. High temperature annealing of the ternary results in dual-phase regions of Be{sub 12}(Nb,Zr) + Be{sub 17}(NbZr){sub 2} or Be{sub 13}(Zr,Nb) + Be{sub 17}(Zr,Nb){sub 2}, but the coexistence of Be{sub 12}(Nb,Zr) + Be{sub 13}(Zr,Nb) has not been observed. 10 refs., 5 figs.

• Research Organization: Pacific Northwest Lab., Richland, WA (United States)
• Sponsoring Organization: DOE; DOD; USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5061121
• Report Number(s): PNL-SA-19088; CONF-910938--6; ON: DE92002146
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOY SYSTEMS
ALLOYS
BERYLLIUM ALLOYS
BERYLLIUM BASE ALLOYS
BINARY ALLOY SYSTEMS
DEPOSITION
INTERMETALLIC COMPOUNDS
NIOBIUM ALLOYS
PHASE STABILITY
STABILITY
TERNARY ALLOY SYSTEMS
ZIRCONIUM ALLOYS