Melt-spun Nd9.5Fe81Zr3B6.5 ribbons were prepared by the melt-spinning technique. The phase evolution and magnetic properties were studied by X-ray diffraction, differential scanning calorimetry, transmission electron ...Melt-spun Nd9.5Fe81Zr3B6.5 ribbons were prepared by the melt-spinning technique. The phase evolution and magnetic properties were studied by X-ray diffraction, differential scanning calorimetry, transmission electron microscopy observations, and magnetization measurements. It is indicated that melt spinning at different wheel velocities caused the as-quenched ribbons to have distinctive structure. The phase transformation of the ribbons during annealing takes place in two steps: α-Fe transforms from the amorphous phase firstly, followed by formation of Nd2Fe14B phase. With increasing the initial quenching rate, the microstructure of optimally heat treated ribbons becomes coarser, which results in the weakening of the exchange coupling effect between the hard and soft phase. This leads to drastic deterioration of magnetic properties of annealed ribbons with increasing the initial quenching rate.展开更多
The Nd Fe B/Co multilayer films were prepared by magnetron sputtering. After that, the samples were annealed at 600 ℃ for 20 min. The surface morphology, phase structures and magnetic properties of Mo(50 nm)/[Nd F...The Nd Fe B/Co multilayer films were prepared by magnetron sputtering. After that, the samples were annealed at 600 ℃ for 20 min. The surface morphology, phase structures and magnetic properties of Mo(50 nm)/[Nd Fe B(100 nm)/Co(y)]×10/Mo(50 nm) thin films were researched by AFM, XRD and VSM, respectively. The results show that the films show stronger perpendicular magnetic anisotropy. When the thickness of Co layers is 10 nm, the coercivity Hc⊥ is the maximum, 295 k A/m. However, for y=10-20, the reduced remanence M/Ms of films has increased. When the thickness of Co layers is 20-30 nm, the Nd Fe B/Co multilayer films obtained more superior magnetic properties with M/Ms =0.95.展开更多
基金Projects(51201109,51001076)supported by the National Natural Science Foundation of ChinaProject(T201108)supported by Shenzhen Key Laboratory of Special Functional Materials,China
文摘Melt-spun Nd9.5Fe81Zr3B6.5 ribbons were prepared by the melt-spinning technique. The phase evolution and magnetic properties were studied by X-ray diffraction, differential scanning calorimetry, transmission electron microscopy observations, and magnetization measurements. It is indicated that melt spinning at different wheel velocities caused the as-quenched ribbons to have distinctive structure. The phase transformation of the ribbons during annealing takes place in two steps: α-Fe transforms from the amorphous phase firstly, followed by formation of Nd2Fe14B phase. With increasing the initial quenching rate, the microstructure of optimally heat treated ribbons becomes coarser, which results in the weakening of the exchange coupling effect between the hard and soft phase. This leads to drastic deterioration of magnetic properties of annealed ribbons with increasing the initial quenching rate.
文摘The Nd Fe B/Co multilayer films were prepared by magnetron sputtering. After that, the samples were annealed at 600 ℃ for 20 min. The surface morphology, phase structures and magnetic properties of Mo(50 nm)/[Nd Fe B(100 nm)/Co(y)]×10/Mo(50 nm) thin films were researched by AFM, XRD and VSM, respectively. The results show that the films show stronger perpendicular magnetic anisotropy. When the thickness of Co layers is 10 nm, the coercivity Hc⊥ is the maximum, 295 k A/m. However, for y=10-20, the reduced remanence M/Ms of films has increased. When the thickness of Co layers is 20-30 nm, the Nd Fe B/Co multilayer films obtained more superior magnetic properties with M/Ms =0.95.