Phase formation in mechanically alloyed Nb-Al powders

Journal Article · Mon Oct 10 00:00:00 EDT 1988 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.99989· OSTI ID:6936639

Hellstern, E; Schultz, L; Bormann, R; Lee, D

Nb-Al alloys have been prepared by mechanical alloying of elemental crystalline powders and investigated with x-ray diffraction and transmission electron microscopy. Crystalline equilibrium phases form for Al-rich alloys. Amorphous phase formation is observed for the Nb/sub 50/Al/sub 50/ composition. Mechanically alloyed powders with more than 70 at. % Nb exhibit the metastable bcc (A2) solid solution which transforms after thermal annealing into the A15 phase. Formation of the different phases can be understood by considering the free-energy curves of the amorphous and bcc phases as calculated from the phase diagram and additional thermodynamic data.

• Research Organization: Siemens AG, Research Laboratories, Erlangen, West Germany
• OSTI ID: 6936639
• Journal Information: Appl. Phys. Lett.; (United States), Journal Name: Appl. Phys. Lett.; (United States) Vol. 53:15; ISSN APPLA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
360102 -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
ALUMINIUM ALLOYS
AMORPHOUS STATE
ANNEALING
DATA
ENERGY
EXPERIMENTAL DATA
FABRICATION
FREE ENERGY
HEAT TREATMENTS
INFORMATION
METALLURGY
NIOBIUM ALLOYS
NIOBIUM BASE ALLOYS
NUMERICAL DATA
PHASE STUDIES
PHYSICAL PROPERTIES
POWDER METALLURGY
THERMODYNAMIC PROPERTIES