Heat treatment of amorphous Al85Y5Ni10 and Al85Y10Ni5 alloys

Microstructural changes during annealing of amorphous Al85Y5Ni10 and Al85Y10Ni5 alloy ribbons have been studied by a combination of differential scanning calorimetry, transmission electron microscopy and X-tay diffractometry. As-solidified melt spun Al(85)Y5Ni(10) consists of some atomic clusters or microcrystals embedded in an amorphous matrix, resulting in a shoulder on the amorphous halo diffraction pattern. The alloy crystallizes by primary crystallization of an fee alpha solid solution followed by precipitation of orthorhombic Al3Ni. As solidified melt spun Al85Y10Ni5 consists of a fully amorphous structure with no shoulder on the amorphous halo diffraction pattern. The alloy crystallizes by primary crystallization of an fee alpha solid solution followed by an eutectic reaction to form a and hexagonal Al3Y. (C) 1997 Elsevier Science S.A.