Glass‐Forming Ability and Crystallization Behavior of Al₈₆Ni₉La₅ Metallic Glass with Si Addition

The glass‐forming ability (GFA) of (Al₈₆Ni₉La₅)_100−xSi_x alloys, where x = 0.0, 0.2, 0.5, 1.0 and 2.0, were determined with the crystallization behavior of these alloys. As the Si content increases, the GFA reaches a maximum at x = 0.2 and then continuously decreases. The thermal stability of the metallic glass is also deteriorated owing to the Si addition, which is accompanied by a gradual disappearance of the glass transition in the DSC traces. It is demonstrated that the peak in GFA at x = 0.2 is due to the increase in atomic packing efficiency while the deterioration of GFA at larger x is related to the chemical action between Si and other elements, which leads to a heterogeneous amorphous structure and a significant increase in microhardness at x = 0.5.