Title :
The influence of Tb substitution on the magnetic properties of nanocomposite Pr2Fe14B/α-Fe magnets
Author :
Jin, Z.Q. ; Okumura, H. ; Hadjipanayis, G.C.
Author_Institution :
Dept. of Phys. & Astron., Delaware Univ., Newark, DE, USA
fDate :
7/1/2001 12:00:00 AM
Abstract :
Tb-doped (Pr,Tb)2Fe14Be/α-Fe nanocomposite ribbons have been synthesized by melt-spinning Pr8-x TbxFe86B6 alloys at low speeds. The effects of Tb substitution and rapid annealing on the magnetic properties of the composites were investigated. With a small addition of Tb, the Curie temperature of hard phase increases slightly, the saturation magnetization decreases but the coercivity increases due to a higher anisotropy field and a refinement of grain size, leading to an enhancement in the energy product. Transmission electron microscopy revealed a finer and more homogeneous (Pr,Tb)2Fe14B/α-Fe microstructure with an average grain size in the range from 20 to 40 nm. The best results are obtained with a room temperature coercivity of 6.6 kOe, Mr=118 emu/g, and (BH)m=15.2 MGOe in Pr7Tb1Fe86B6 sample annealed at 800°C for 1 minute
Keywords :
Curie temperature; annealing; boron alloys; coercive force; composite materials; grain size; iron; iron alloys; magnetic anisotropy; magnetisation; melt spinning; nanostructured materials; permanent magnets; praseodymium alloys; terbium alloys; transmission electron microscopy; (PrTb)2Fe14B-Fe; 800 C; Curie temperature; Pr2Fe14B/α-Fe nanocomposite ribbon; Tb substitution; anisotropy field; annealing; coercivity; energy product; grain size; magnetic properties; melt spinning; microstructure; permanent magnet; saturation magnetization; transmission electron microscopy; Anisotropic magnetoresistance; Annealing; Coercive force; Electrons; Grain size; Iron alloys; Magnetic properties; Refining; Saturation magnetization; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
