Variation of Avrami exponent for crystallization of melt-spun amorphous ribbons

Abstract

Crystallization process of a melt-spun amorphous NiP ribbon was studied by using differential scanning calorimetry. Local Avrami exponents for the crystallization were determined. It was found that the early stage of the transformation was dominated by surface nucleation and growth, middle stage was bulk nucleation and growth, and last stage was crystal growth in bulk. Variations of local Avrami exponents with baseline determination, anneal temperature and pre-anneal treatment were demonstrated and analyzed.