Characterization of β″ precipitate phase in a Mg–Dy–Gd–Nd alloy

The morphology and crystal structure of β″ precipitate phases in a Mg–Dy–Gd–Nd system have been studied using transmission electron microscopy and X-ray diffraction. Three orientation relationships have been observed between β″ precipitate phases and the α matrix phase with the habit plane parallel to {112¯0}α. The orientation relationship between the β″ precipitates and the matrix is [0001]β″//[0001]α, [11¯00]β″//[11¯00]α. The structure of the β″phase, with the interspaces between Dy/Gd/Nd atoms filled with magnesium atoms, is completely consistent with that of the matrix.