Effects of Hf on phase structure and magnetic performance of nanocrystalline SmCo-type alloy.

The effects of Hf doping on the phase constitution and its evolution of the SmCoHf (0 ≤ x ≤ 0.5) nanocrystalline alloys were investigated. It was found that a single TbCu-type metastable phase can be stabilized in the nanocrystalline SmCoHf alloys with x ≤ 0.25, and the phase decomposition occurs at higher Hf doping contents. The Hf doping plays a significant role in inhibiting grain growth at high temperatures, which is favorable for the high-temperature magnetic properties. The metastable phase is stabilized by the combined effects of nanostructuring and Hf doping. Moreover, the magnetic performance is increased due to the pinning effect and the high magnetocrystalline anisotropy of the stabilized TbCu-type phase. [ABSTRACT FROM AUTHOR]