Dependences of the crystallization behavior of Al-Ni-La amorphous alloys on La and Ni contents

Crystallization behaviors of Al-Ni-La amorphous alloys with a fixed Ni (La) content of 6 at.% were investigated by X-ray diffraction and differential scanning calorimeter when the La (Ni) content changes from 3 to 9 at.%. The results show that the thermal stability of the amorphous alloys monotonically increases with increasing the La (Ni) content. Glass transition only exists in the alloys with the La (Ni) content higher than 6 at.%. La plays a more significant role than Ni in promoting the glass-forming ability, improving the thermal stability, stabilizing the supercooled liquid region, depressing the precipitation of fcc-Al in the first crystallization process and increasing the apparent activation energy of the first reaction. (c) 2007 Elsevier B.V. All rights reserved.