Effect of quenched-in nuclei on the crystallisation kinetics of metallic glasses

Abstract

The crystallisation behaviour of a-Fe78Si9B11C2 has been studied using differential scanning calorimetry, Mossbauer spectroscopy and length change measurement. The isothermal kinetics of crystallisation are followed by measuring the change in length of the specimen. Data have been analysed in terms of a theoretical model which takes into account the effect of crystal growth on pre-existing nuclei. Quenched-in nuclei are found to affect the kinetics of crystallisation significantly. A detailed analysis of the data yields activation energies for both nucleation and growth of crystallites, information that is normally obtainable only through TEM.