Thermokinetic analysis of the multistep crystallization of a NANOPERM-type ribbon

The crystallization of the as-quenched Fe76Mo8Cu1B15 ribbon proceeds in four independent transformation steps, which however mutually overlap both in the temperature and time scales. A complex thermokinetic method is presented, by which the individual transformations could be experimentally separated and characterized. The kinetics and mechanism of the individual transformations have been determined. Both linear-heating and isothermal differential scanning calorimetry was used. As-prepared as well as heat-treated samples were characterized by transmission electron microscopy, X-ray diffraction and Mössbauer spectroscopy.