Investigation on the Cu-rich phase in annealed Fe73.5Cu1Mo3Si13.5B9 alloy

Strong experimental evidence suggests that we discovered a new crystalline phase, Cu-rich phase, in nanocrystalline Fe73.5Cu1Mo3Si13.5B9 alloy at the optimum magnetic stage. Experimental work was carried out using selected area electron diffraction (SAED) of transmission electron microscopy and X-ray diffraction (XRD). This Cu-rich phase possesses fee structure and exists randomly in orientation; its size, volume fraction and Cu content increase as the annealing temperature is increased. When the annealing temperature increases to 600 degrees C, the size and volume fraction of the Cu-rich phase reach 6.4 nm and 2.5%, respectively; at the same time, the lattice parameter is 0.3620 nm.