J. Phys. Colloques
Volume 48, Numéro C3, Septembre 19874th International Aluminium Lithium Conference
|Page(s)||C3-481 - C3-488|
J. Phys. Colloques 48 (1987) C3-481-C3-488
THE ICOSAHEDRAL Al-Li-Cu PHASEF.W. GAYLE
Reynolds Metals Company, Metallurgy Laboratory, Richmond, VA 23219, U.S.A.
The common grain boundary precipitate in commercial Al-Li-Cu-(Mg) alloys which is responsible for detrimental precipitate-free zones is the icosahedral Al-Li-Cu phase designated T2. The present work discusses the growth of the T2 phase as large, faceted single quasicrystals and reviews results of morphological analyses and high resolution x-ray studies. These results confirm the icosahedral point symmetry of the phase and allow comment on the atomic structure and the disorder which appears to be inherent in the phase.