THERMODYNAMIC PROPERTIES OF THE TANTALUM AND TUNGSTEN BORIDES

Journal Article · Tue May 01 04:00:00 EDT 1962 · Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol.

DOI:https://doi.org/10.1149/1.2425442· OSTI ID:4820717

Leitnaker, J M; Bowman, M G; Gilles, P W

Experiments involving high-vacuum heating of samples of the tantalum borides, or tantalum and ZrB/sub 2/, or tungsten and ZrB/sub 2/ are discussed. Identification of the resulting phases by x-ray diffraction procedures served to indicate what chemical reactions occurred and what products can exist together at the test temperature. The results were used to obtain limiting values for the heats of formation of the various phases. The limits on heats of formation based on -76.7 for ZrB/sub 2/ are: Ta/sub 2.4/B, Ta/sub 1.6/B, and TaB = -64.9 to-38.4, 1/2TaB/sub 2/ =-51.7 to -22.7, and W/sub 2/B = -26.0 to -20 kcal/mole. The results indicate greater stability for the tantalum borides than were reported previously and have set bounding limits on the stability of lower borides of both tantalum and tungsten. (P.C.H.)

• Research Organization: Los Alamos Scientific Lab., N. Mex.
• Sponsoring Organization: USDOE
• NSA Number: NSA-16-018058
• OSTI ID: 4820717
• Journal Information: Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol., Journal Name: Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol. Vol. Vol: 109; ISSN JESOA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALLOTROPY
DIFFRACTION
FORMATION HEAT
METALS, CERAMICS, AND OTHER MATERIALS
STABILITY
TANTALUM
TANTALUM BORIDES
THERMODYNAMICS
TUNGSTEN
TUNGSTEN BORIDES
X RADIATION
ZIRCONIUM BORIDES