The crystallization behaviour of amorphous melt spun Fe82−x−yCr18ZrxBy (x=0–8, y=10–20) ribbons have been investigated using differential scanning calorimetry. The crystallization temperature and
crystallization behaviour change with varzing Zr and B content.
The microstructural development during annealing of amorphous Fe64Cr18Zr8B10 has been investigated by a combination of transmission electron microscopy and energy dispersive X-ray microanalysis. Isothermal
annealing for 2 h at temperatures in the range 600–1000°C produces a variety of different microstructures depending on the
annealing temperature. At 600°C, the amorphous alloy partially crystallizes to a form a microstructure consisting of 9 nm
sized bee ferrite grains embedded in an amorphous matrix. At temperatures in the range 700–900°C, the alloy microstructure
transforms into a mixture of bee ferrite, faulted fcc MB12 boride particles and tetragonal M3B boride particles. At 1000°C, the faulted fcc MB12 boride particles are replaced by orthorhombic M4B boride particles.