Atomic‐Scale Insight into Structure and Interface of Al2Y Phase in an Mg–Al–Y Alloy. Issue 4 (8th February 2018) - Peng, Z. Z.
Abstract : Atomic‐scale structure of Al2 Y phase and its interface with magnesium matrix in an Mg–1Al–6.2Y (wt%) alloy have been investigated using scanning transmission electron microscopy (STEM) and density‐functional theory (DFT). Apart from micro‐sized Al2 Y particles in the interior of grains or along grain boundaries, nano‐sized Al2 Y lamella with a large aspect ratio precipitates within the grains. Y − enriched stacking faults are introduced at the lamellar Al2 Y/Mg interface due to 0.07% lattice misfit between (022)Al2Y and ( 0 1 ¯ 10 ) Mg planes. The first‐principles simulation clarifies that Al2 Y/Mg interface is energetically occupied by Al atoms other than Y atoms. Abstract : Atomic‐scale structure of Al2Y phase and its interface with magnesium matrix in an Mg–1Al–6.2Y (wt%) alloy have been investigated using scanning transmission electron microscopy (STEM) and density‐functional theory (DFT). Some micro‐sized Al2Y particles, as well as all the nano‐sized Al2Y precipitates, have good orientation relationship with matrix. The interfacial structure of Al2Y with the magnesium matrix is further rationalized by First‐principle simulation, demonstrating that Al2Y/Mg interface is energetically occupied by Al atoms other than Y atoms.