A series of doped barium hexaferrites BaFe12-2xMnxSnxO19 (x = 0.0-1.0) particles were prepared by the co-precipitation/molten salt method. The particle size and crystalline of the samples BaFe12-2xMnxSnxO19 decrease...A series of doped barium hexaferrites BaFe12-2xMnxSnxO19 (x = 0.0-1.0) particles were prepared by the co-precipitation/molten salt method. The particle size and crystalline of the samples BaFe12-2xMnxSnxO19 decrease with an increase in the doping amount x. When x is less than 0.8, the pure BaFe12-2xMnxSnxO19 particles with hexagonal plate morphology are obtained. The effects of substitution on magnetic properties were evaluated and compared to nomal BaFe12O19. The specific magnetizations (Ms) of doped materials have been significantly improved. Among all these compositions, the BaFe10.4Mn0.8Sn0.8O19 sample has the highest Ms value of 81.8 A?m2?kg-1 at room temperature and its intrinsic coercivity (Hc) is 44.5 kA?m-1. The as-prepared doped barium ferrites exhibit a low temperature coefficient of coercivity close to zero. The coercivity is independent of temperature when x is in the a range 0.5-0.7.展开更多
The electrodeposition of erbium on molybdenum electrodes and the formation of Mg-Li-Er alloys were investigated in LiCl-KCl molten salts. At a molybdenum electrode, the electroreduction of Er (III) proceeded in a on...The electrodeposition of erbium on molybdenum electrodes and the formation of Mg-Li-Er alloys were investigated in LiCl-KCl molten salts. At a molybdenum electrode, the electroreduction of Er (III) proceeded in a one-step process involving three electrons. The diffu-sion coefficient of erbium ions in the melts was determined by cyclic voltammetry, chronopotentiometry and chronoamperometry respectively. Cyclic voltammograms (CVs) showed that the underpotential deposition (UPD) of lithium on pre-deposited Mg-Er alloy led to the formation of a Mg-Li-Er alloy. X-ray diffraction (XRD) indicated that Er5Mg24 phase was formed via potentiostatic electrolysis. Scanning electron microscopy (SEM) showed that Er atoms mainly concentrated at the grain boundaries while Mg element evenly located in the alloy.展开更多
Three kinds of ultra-light Mg-Li wrought alloys,Mg-5.5Li-3Al-1Zn-1Ce,Mg-7.0Li-3Al-1Zn-1Ce and Mg-10.5Li-3Al-1Zn-1Ce,were prepared by vacuum induction melting furnace;then the alloys were extruded and rolled.The micros...Three kinds of ultra-light Mg-Li wrought alloys,Mg-5.5Li-3Al-1Zn-1Ce,Mg-7.0Li-3Al-1Zn-1Ce and Mg-10.5Li-3Al-1Zn-1Ce,were prepared by vacuum induction melting furnace;then the alloys were extruded and rolled.The microstructures and properties of these alloys were studied.The results indicate that the Mg-5.5Li3Al-1Zn-1Ce alloy has the highest strength,the Mg-10.5Li-3Al-1Zn-1Ce alloy has maximum elongation,and the Mg-7.0Li-3Al-1Zn-1Ce alloy has good comprehensive performance.Rolling deformation can increase strength further after extrusion deformation.展开更多
基金Funded by National Natural Science Foundation of China (Nos.20801016, 20701013, and 60971020)Postdoctoral Foundation of Heilongjiang Province(No. LRB07-231)Fundamental Research Funds for the Central Universities(No.HEUCF201210010)
文摘A series of doped barium hexaferrites BaFe12-2xMnxSnxO19 (x = 0.0-1.0) particles were prepared by the co-precipitation/molten salt method. The particle size and crystalline of the samples BaFe12-2xMnxSnxO19 decrease with an increase in the doping amount x. When x is less than 0.8, the pure BaFe12-2xMnxSnxO19 particles with hexagonal plate morphology are obtained. The effects of substitution on magnetic properties were evaluated and compared to nomal BaFe12O19. The specific magnetizations (Ms) of doped materials have been significantly improved. Among all these compositions, the BaFe10.4Mn0.8Sn0.8O19 sample has the highest Ms value of 81.8 A?m2?kg-1 at room temperature and its intrinsic coercivity (Hc) is 44.5 kA?m-1. The as-prepared doped barium ferrites exhibit a low temperature coefficient of coercivity close to zero. The coercivity is independent of temperature when x is in the a range 0.5-0.7.
基金Project supported by by the Fundamental Research funds for the Central Universities (HEUCF101002)the National Natural Science Foundation of China (50871033)
文摘The electrodeposition of erbium on molybdenum electrodes and the formation of Mg-Li-Er alloys were investigated in LiCl-KCl molten salts. At a molybdenum electrode, the electroreduction of Er (III) proceeded in a one-step process involving three electrons. The diffu-sion coefficient of erbium ions in the melts was determined by cyclic voltammetry, chronopotentiometry and chronoamperometry respectively. Cyclic voltammograms (CVs) showed that the underpotential deposition (UPD) of lithium on pre-deposited Mg-Er alloy led to the formation of a Mg-Li-Er alloy. X-ray diffraction (XRD) indicated that Er5Mg24 phase was formed via potentiostatic electrolysis. Scanning electron microscopy (SEM) showed that Er atoms mainly concentrated at the grain boundaries while Mg element evenly located in the alloy.
基金the Project of Science and Technology of Heilongjiang Province Education Department(No. 11553054)
文摘Three kinds of ultra-light Mg-Li wrought alloys,Mg-5.5Li-3Al-1Zn-1Ce,Mg-7.0Li-3Al-1Zn-1Ce and Mg-10.5Li-3Al-1Zn-1Ce,were prepared by vacuum induction melting furnace;then the alloys were extruded and rolled.The microstructures and properties of these alloys were studied.The results indicate that the Mg-5.5Li3Al-1Zn-1Ce alloy has the highest strength,the Mg-10.5Li-3Al-1Zn-1Ce alloy has maximum elongation,and the Mg-7.0Li-3Al-1Zn-1Ce alloy has good comprehensive performance.Rolling deformation can increase strength further after extrusion deformation.