Nanocrystallization of amorphous alloys using microwaves: In situ time-resolved synchrotron radiation studies

Important energy and time savings can be achieved with the thermal treatment of materials by replacing conventional heating methods with microwave heating. The nanocrystallization of Co-Fe-W-B amorphous alloy powders under microwave irradiation was followed for the first time by in situ time-resolved synchrotron radiation powder diffraction. It is shown that even a very short exposure to the electromagnetic field (single pulse microwave application) typically of the order of a few seconds is sufficient to obtain the bulk nano-crystalline state. A metastable high-temperature Co-W-B orthorhombic phase forms during the microwave heating, which gradually transforms to the tetragonal Co2B stable phase.