Micro-structural changes in the amorphous Fe-based alloy 2605S3A prior to crystallization Part 1. Differential scanning calorimetry, heating treatment, X-ray diffraction and Vickers micro-hardness

Clusters of 24 and 32 mono-vacancies in the amorphous and crystalline states of the 2605S3A alloy, respectively, having 0.44 nm mean radii and a mean relative concentration of clusters of C = 1.68x10 8 atoms -1 between these states were measured by the positron annihilation process. Slight variations of size and of the concentration of these clusters were the source of micro-structural changes in the alloy as reflected in its mechanical properties, magnetic properties and phase transitions. These results are analyzed in terms of the micro-structural changes occurring in the alloy using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Moreover, nanometric changes in the sample are detected by using Mossbauer spectroscopy and Vickers micro-hardness measurements.