Nanocrystalline soft magnetic Fe-Si-B-P-Cu alloys with high B of 1.8-1.9T contributable to energy saving

Melt-spun Fe ₈₅Si _1-2B _8-11P _1-4Cu ₁ alloys have unusual hetro-amorphous structures which can transfoto nanocrystalline structures composed of α-Fe grains with less than about 25 nm in size with crystallization. Especially, Fe ₈₅Si _1-2B _8-11P _1-4Cu ₁ nanocrystalline soft magnetic alloys prepared by crystallizing an as-quenched nanohetero-amorphous phase including a large amount of extremely small α-Fe grains (less than 2-3 nm in size) exhibit high B ₈₀₀ of 1.8-1.9 T (at 800 A/m) almost comparable to those of commercial oriented silicon steels and significantly higher than those of non-oriented silicon steels, along with extremely low core loss (W) which is 1/2-1/3 smaller than that of the highest-grade oriented silicon steel and about one-order smaller than those of non-oriented silicon steels at maximum flux density of 1.7 T. The nanocrystalline alloys with lower materials cost due to absence of rare-metals are expected to not only contribute to significant energy-saving and reduction of CO ₂ emission through reduction in W but also be useful to conserve the earth's resources and environment.