Phase constitution in melt-spun Al-10 wt% Y

A rapidly solidified Al-10 wt% Y alloy has been examined by X-ray diffraction and analytical electron microscopy. An α-Al cellular structure was obtained with intercellular ‘Al₄Y’. The ‘Al₄Y’ was determined to be tetragonal with a space group of 14/mmrn, in agreement with some earlier studies. An orientation relationship with [011] Al nearly parallel to [110] Al₄Y was identified. An additional phase which is morphologically and chemically similar to the tetragonal Al₄Y was also observed in small quantities. This was tentatively identified as orthorhombic, but insufficient data were available to determine fully the crystal structure.