| Double-phase nanocomposite permanent magnet materials cause wide attention due to excellent magnetic properties. (For example (BH)_max can get 1090 kJ/m3 theoretically, which exceeds any simple-phase permanent magnet materials.). How to produce permanent magnets with high properties and cheapness is one of the hot points at present. The factors, such as component, structure of phase, organization which include grain shape, grain size, amount and distribution of every phase etc, influence magnetic properties, while permanent magnets that are produced by different methods and annealing process have different organizations, in other words they have different magnetic properties. Double-phase nanocomposite permanent magnetic materials were produced by the single roller rapid quenching and annealing in this dissertation, Relationship between all influent factors and magnetic properties was researched by changing annealing process and adding elements, including different kinds of rare-earth elements Tb and Dy and transitional elements Co and Ga etc.Nd4.5Fe77.5-xTbxB18 (x=0; 1) alloys were prepared by the single roller rapid quenching method and then analyzing relationship between annealing temperature, annealing time, addition element Tb and magnetic properties. To Nd4.5Fe77.5B18 and Nd4.5Fe76.5Tb1B18 alloys, it is critical to decrease crystalline size as possible under the precondition of crystallization integrated in order to get optimal magnetic properties annealing time unchangeable. The annealing temperature is passed through lowly either is overtopped. The annealing temperature is unchangeable, annealing time passes through to develop either passes through brief not benefiting sufficient crystalline substanceization and control crystalline grain size. To the compound metal that lets drop the tall B of Nd, Be living below the tall vacuum condition, spray head caliber is 0.6mm, the spray head against the roll is 5mm, spray head pressure is 0.09MPa, the rate of the roll is 22m/s, rolled Non-slight girdle of crystalline substance's magnetic properties are optimal underthe condition of 550°C and annealing time lOmin. By doping 1 percent Tb, coercive of compound metal is improved obviously, but crystalline substance temperature and crystalline substance time effect to the compound metal unobvious.The effect of annealing process parameter on magnetic properties of Nd4.5Fe77.5-xGaxBi8 (x=0; 1) alloys was tested by a differential thermal analysis instrument, X-ray Diffractometer and a vibrating sample magnetometer (VSM). The results show that doping 1% Ga influenced crystalline substance action of double-phase nanocomposite permanent magnetic materials. There isn't almost disparity between the first exothermic top temperature of two kind of samples, but the second exothermic top temperature changes bigly as component of samples changes. When Ga is doped in the alloys, viscosity is increased, so atom's divergency is difficult in the alloys in the crystallization process, which crystallizing temperature of Nd2Fej4B phase and Fe3B phase is lagged, hence separation temperature is increased.Analying the effect of annealing process on the magnetic properties of Nd4.5Fe76.5-xCoxDyiBi8 (x=0, 3), we found that the magnetic effect of alloy doped Co maintain degradution tendency, however, the velocity of degradution is slow. The remanence and coercivity of Nd5Fe74Co3DyiBi7 is more than Nd5Fe77Big's under two kinds of conditions (fixing annealing time, changing annealing temperature; fixing annealing temperature, changing annealing time). Nonisotropic field of Dy2Fei4B because of doping Dy is more than Nd2Fei4B's, secondly microstructure of alloys is developed and crystalline grain is diminished after doping Dy.
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