Studies on the bulk nanocrystalline Ni-Fe-Co alloy prepared by mechanical alloying-sintering-hot rolling route (original) (raw)
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A new nanocrystalline Fe-based soft magnetic alloy is discussed here. Ingots of nanocrystalline alloys ͑FeCu͒ 80 Zr x Si 20−x ͑x = 5, 6, and 8͒ were prepared by arc melting. The ingots were remelted and cast into 25-30 m thick ribbons by a single roller melt spinning method. X-ray diffraction ͑XRD͒ revealed the as-spun ribbons to be amorphous. The structural evolution of these samples was studied by XRD and transmission electron microscopy ͑TEM͒ after annealing at 450, 480, and 550°C. XRD shows the primary nanocrystallization product to be the ␣-Fe͑Si͒ phase. The grain size was observed by TEM to be ϳ10 nm after annealing at 480°C for 1 h and 14 nm after 550°C for 1 h. ac soft magnetic properties were measured using a Walker AMH 401 ac permeameter. The core loss at an exciting frequency f = 100 kHz and maximum induction B m = 1 kG was determined to be less than 19 W / kg.