真空熔体快淬+HDDR方法制备各向异性Nd-Dy-Fe-Co-Zr-B合金磁性能研究

　　真空熔体快淬+HDDR方法制备各向异性Nd-Dy-Fe-Co-Zr-B合金磁性能研究
　　The anisotropic permanent magnetic alloys were prepared by melt-spun + HDDR method. The magnetic properties of the samples were measured by Vibrating Sample Magnetometer (VSM). The phases of the samples were studied using X-Ray diffraction (XRD). The particle size distribution and the morphology of the samples were observed by Transmission Electron Microscopic (TEM).The melt-spun ribbons with normal composition of Nd12.7Dy0.3Fe64.9Co16Zr0.1B6 were prepared at surface velocity 8m/s. In order to study the effect of HDDR condition on the magnetic properties of the samples, the Neodymium Magnets melt-spun ribbons were treated at different hydrogen pressure and different temperature during HD process, at different temperature and different times during DR process. The influence of Co content on the magnetic properties of Nd12Dy1Fe80.9-xCoxZr0.1B6 alloy was also studied in this thesis. The main results are as follows:(1) During HD process, the melt spun ribbon absorbed hydrogen and decomposed into NdH2, (Fe, Co)2B,α-(Fe, Co) and some undecomposed 2:14:1 phase. Those undecomposed 2:14:1 phase could be the nucleation centre during DR process while the decomposed mixture formed c-axis texture of Nd2(Fe, Co)14B. After HDDR process, the original flaky crystal has been destroyed and the fine spherical particles were obtained.(2) The magnetic properties of the samples were enhanced greatly after HDDR process due to the improvement of the microstructure and the increase of the grain orientation of the samples. The best magnetic properties of (BH)max=21.170 MGOe, Br = 1.090T , Hci = 748kA/m for Nd12.7Dy0.3Fe64.9Co16Zr0.1B6 sample were obtained under the following HDDR process: The melt-spun Nd12.7Dy0.3Fe64.9Co16B6Zr0.1 ribbon was heated up to 800℃in vacuum.
　　Then the sample subjected to HD process for 120 minute under the hydrogen pressure of 0.05MPa. After that, keep the sample in the 0.03MPa argon environment at this temperature for 30 minute. neodymium prices Finally, keep the sample at the same temperature in the vacuum for 30 minutes and then furnace cooled.(3) The magnetic properties of melt-spun+ HDDR treated Nd12Dy1Fe80.9-xCoxZr0.1B6 sample were studied. The experimental results showed that the energy product, the remanence and the coercive force of the sample can be improved simultaneously by substitute Fe element by moderate Co. In addition, the Curie temperature of the sample enhanced greatly by substitute Fe element by moderate Co.