Nanocrystalline Soft Magnetic Fe-Si-B-P-Cu Alloys With High $B$ of 1.8–1.9T Contributable to Energy Saving

摘要

Melt-spun ${rm Fe}_{85}{rm Si}_{1-2}{rm B}_{8-11}{rm P}_{1-4}{rm Cu}_{1}$ alloys have unusual hetro-amorphous structures which can transform to nanocrystalline structures composed of $alpha-{rm Fe}$ grains with less than about 25 nm in size with crystallization. Especially, ${rm Fe}_{85}{rm Si}_{1-2}{rm B}_{8-11}{rm P}_{1-4}{rm Cu}_{1}$ nanocrystalline soft magnetic alloys prepared by crystallizing an as-quenched nanohetero-amorphous phase including a large amount of extremely small $alpha-{rm Fe}$ 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 ${rm CO}_{2}$ emission through reduction in $W$ but also be useful to conserve the earth's resources and environment.