Structure Maps and Phase Stability in AlTi3 Alloyed with Rare-Earth Elements

摘要

Rare-earth elements including Y, Er and Sc were added to AlTi sub 3 for stabilizing the L1 sub 2 ordered crystal structure, as predicted by the AB sub 3 structure map. The crystal structure and phase composition in the AlTi sub 3 alloys were studied by electron microprobe analysis, x-ray diffraction and TEM. All the results indicate that rare-earth additions are unable to change the crystal structure of AlTi sub 3 from DO sub 19 to L1 sub 2 . The failure to stabilize the L1 sub 2 structure cannot be simply related to atomic size and solubility limit of the rare-earth elements in AlTi sub 3 . 17 refs., 5 figs., 1 tab. (ERA citation 14:019883)