Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

THE THERMAL STABILITY OF ScF$sub 3$ AND ITS REACTION WITH MgF$sub 2$ (in Russian)

Journal Article · · Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals
OSTI ID:4716295
;
ScF/sub 3/ was prepared by reacting Sc/sub 2/O/sub 3/ with 40% HF, and MgF/sub 2/ was prepared by reacting MgCO/sub 3/ with 40% HF. A thermogravimetric analysis showed that ScF/sub 3/ begins to lose weight slowly at about 400 un. Concent 85% C; the weight loss becomes much more rapid at 650 un. Concent 85% C. The ScF/sub 3/ is directly converted to Sc/sub 2/O/sub 3/ without formation of an intermediate oxyfluoride. The rate of conversion of ScF/sub 3/ to Sc/sub 2/O/sub 3/ depends on the temperature. Complete conversion takes 2.5 hours at 900 un. Concent 85% , 5.3 hours at 800 un. Concent 85% , and 11 hours at 700 un. Concent 85% C. It was found that ScF/sub 3/ melts at a temperature of 1530 450 deg C in a 20 un. Concent 85% C, and undergoes a polymorphic conversion at 1350 un. Concent 85% C. The phase diagram of the ScF/sub 3/- MgF/sub 2/ system was determined. The solubility of ScF/sub 3/ is about 5 mol% in MgF/sub 3/. A eutectic is formed at 34 mol% ScF/sub 3/. The melting point of the eutectic is 1095 un. Concent 85% C. No formation of intermediate phases in the system were observed. The lattice parameters of MgF/sub 2/ (a and c) are 4.613 and 3.081 kX, respectively, which decrease to a = 4.595, and c = 3.041 kX on adding ScF/sub 3/ to the MgF/sub 2/. (TTT)
Research Organization:
Moscow State Univ.
NSA Number:
NSA-17-023321
OSTI ID:
4716295
Journal Information:
Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals, Journal Name: Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals Vol. Vol: 149; ISSN DANKA
Country of Publication:
Country unknown/Code not available
Language:
Russian

Similar Records

METAL-METAL HALIDE SYSTEMS OF GADOLINIUM AND YTTRIUM
Thesis/Dissertation · Sun Dec 31 23:00:00 EST 1961 · OSTI ID:4727091
New phases in the MgF/sub 2/-ScF/sub 3/ system at high pressures
Journal Article · Fri Oct 31 23:00:00 EST 1986 · Inorg. Mater. (Engl. Transl.); (United States) · OSTI ID:7045459
THE EQUILIBRIUM PHASE DIAGRAM, NIOBIUM-ALUMINUM. Final Report
Technical Report · Sun Mar 31 23:00:00 EST 1963 · OSTI ID:4727163

Related Subjects

ALLOTROPY
CHEMICAL REACTIONS
CHEMISTRY
EUTECTICS
HEATING
HIGH TEMPERATURE
HYDROFLUORIC ACID
LATTICES
MAGNESIUM CARBONATES
MAGNESIUM FLUORIDES
MELTING POINTS
PHASE DIAGRAMS
PREPARATION
SCANDIUM FLUORIDES
SCANDIUM OXIDES
SOLUBILITY
STABILITY
TEMPERATURE