Microstructure of Al3Sc with ternary rare-earth additions
نویسنده
چکیده
The microstructure of ternary L12-Al3(Sc1 yREy) intermetallics, where RE is one of the rare-earth elements selected from five light (La, Ce, Nd, Sm or Eu) or two heavy lanthanoids (Yb or Lu), was investigated as a function of RE concentration for 0.02 y 0.75. Alloys with light RE show two phases: L12-Al3(Sc,RE) and D019-Al3(RE,Sc) (or C11b-Al4(Eu,Sc)). Alloys with heavy RE exhibit a single L12Al3(Sc,RE) phase. The maximum RE solubility in the L12 phase is very low (<0.4 at.%) for La, Ce, Nd and Eu, low (3.2 at.%) for Sm and complete solid-solution for Yb and Lu. Both lattice parameter and hardness of the L12-Al3(Sc,RE) phases increase linearly with Sm, Yb or Lu concentration, and the magnitude of both effects correlates with the atomic size mismatch between Sc and RE. 2008 Elsevier Ltd. All rights reserved.
منابع مشابه
Mechanical Properties and Microstructure of Al – Sc with Rare - Earth Element or Al 2 O 3 Additions
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