CRYSTALLIZATION STUDIES ON AMORPHOUS AL-Y-NI AND AL-Y-CU ALLOYS

Al83Y10Ni7, Al80Y10Ni10 and Al80Y10Cu10 alloys were studied by the rapid solidification processing route. The glass-forming ability was found to decrease in the order of alloys mentioned above. Differential scanning calorimetry (DSC) of these amorphous alloys showed that the amorphous phase in Al-Y-Ni alloys has a higher thermal stability when compared to that in Al-Y-Cu alloys. A four-stage crystallization sequence could be identified for the Al-Y-Ni amorphous alloys. Even though the Al80Y10Cu10 alloy showed four exothermic peaks in the DSC study, a definite crystallization sequence could not be arrived at due to the coexistence of many crystalline phases along with the amorphous phase in the melt-spun condition.