Effect of short-range order on the thermal stability in amorphous Ti-Ni alloys

Amorphous Ti1−xNix alloys were prepared by means of melt spinning and studied by means of differential scanning calorimetry. The crystallization temperatures and the activation energies for crystallization were determined over a wide concentration range. The former values were found to vary only slightly with concentration while the latter showed a marked concentration dependence. This difference in behavior is discussed in terms of the occurrence of compositional short-range ordering. It is shown that the activation energy for crystallization is not always a good measure of the thermal stability of amorphous alloys.