Return to search

Phase equilibria in the LiF-AlF₃-Na₃AlF₆-Al₂O₃ system

The phase equilibria relationships in the Li₃A1F₆-A1₂0₃ binary system, the Li₃A1F₆-Na₃AlF₆-A1₂0₃ ternary system and the LiF-A1F₃-Na₃A1F₆-Al₂0₃ quaternary system have been investigated using a combination of X-ray powder diffraction, DTA, quenching and optical microscopy techniques. The compatibility relations at 500°C for the ternary and quaternary systems, the Li₃A1F₆-A1₂0₃ binary system and the ternary liquidus surface were determined. The binary system was found to have a eutectic at 754°C and 1 mole % Al₂0₃. The liquidus surface was found to contain the following three invariant points:

1. eutectic - 66 mole % Li₃A1F₆, 29% Na₃A1F₆, 5% A1₂0₃ and 670°C

2. peritectic - 51 mole % Li₃A1F₆, 42.5% Na₃A1F₆, 65% A1₂0₃ and 683°C

3. reaction point - 65 mole % Li₃A1F₆, 33% Na₃A1F₆, 2% A1₂0₃ and 693°C.

The 500°C isothermal section contains three 3-phase regions and one 2-phase region. The quaternary system contains 7 compatibility tetrahedra at 500°C. / Master of Science

Identiferoai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/64131
Date January 1977
CreatorsCassidy, Roger Thomas
ContributorsMaterials Engineering
PublisherVirginia Polytechnic Institute and State University
Source SetsVirginia Tech Theses and Dissertation
Languageen_US
Detected LanguageEnglish
TypeThesis, Text
Format70 leaves, application/pdf, application/pdf
RightsIn Copyright, http://rightsstatements.org/vocab/InC/1.0/
RelationOCLC# 21796939

Page generated in 0.002 seconds