A systemic investigation was done on the chemistry and crystal structure of boundary phases in sintered Ce9Nd21FebalB1 (wt%) magnets. Ce2Fe14B is believed to be more soluble in the rare-earth (RE)-rich liquid phas...A systemic investigation was done on the chemistry and crystal structure of boundary phases in sintered Ce9Nd21FebalB1 (wt%) magnets. Ce2Fe14B is believed to be more soluble in the rare-earth (RE)-rich liquid phase during the sintering process. Thus, the grain size and oxygen content were controlled via low-temperature sintering, resulting in high coercivity and maximum energy products. In addition, Ce formed massive agglomerations at the triple-point junctions, as confirmed by elemental mapping results. Transmission electron micros- copy (TEM) images indicated the presence of (Ce,Nd)Ox phases at grain boundaries. By controlling the composition and optimizing the preparation process, we successfully obtained Ce9Nd21FebalBx sintered magnets; the prepared magnets exhibited a residual induction, coerciv- ity, and energy product of 1.353 T, 759 kA/m, and 342 kJ/m3, respectively.展开更多
Mn-Cu alloys could exhibit high damping ability and excellent mechanical properties after proper heat treatment. In order to reduce the influence of impurity elements on damping capacity of Mn-Cu alloys, rare ele- men...Mn-Cu alloys could exhibit high damping ability and excellent mechanical properties after proper heat treatment. In order to reduce the influence of impurity elements on damping capacity of Mn-Cu alloys, rare ele- ment cerium (Ce) was added into MnCuNiFe alloys. It is indicated that the contents of C, S and Si which have adverse effects on the damping capacity decrease and the grains are refined with the Ce content increasing. The microstructure of the MnCuNiFeCe alloy was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The damping ability (tane) of the alloy was characterized by dynamical mechanical analyzer (DMA). It is found that the damping ability (tane) retains a very high level which is all above 0.05 from the temperature of -50 to 75 ℃ with the addition of Ce element. It is expected that the Ce alloying MnCuNiFe alloy with refined grains could find wide applications in the field of industry.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 51171048)the National High Technology Research and Development Program of China (No. 2014CB643701)the National Science and Technology Support Program of China (No. 2012BAE02B01)
文摘A systemic investigation was done on the chemistry and crystal structure of boundary phases in sintered Ce9Nd21FebalB1 (wt%) magnets. Ce2Fe14B is believed to be more soluble in the rare-earth (RE)-rich liquid phase during the sintering process. Thus, the grain size and oxygen content were controlled via low-temperature sintering, resulting in high coercivity and maximum energy products. In addition, Ce formed massive agglomerations at the triple-point junctions, as confirmed by elemental mapping results. Transmission electron micros- copy (TEM) images indicated the presence of (Ce,Nd)Ox phases at grain boundaries. By controlling the composition and optimizing the preparation process, we successfully obtained Ce9Nd21FebalBx sintered magnets; the prepared magnets exhibited a residual induction, coerciv- ity, and energy product of 1.353 T, 759 kA/m, and 342 kJ/m3, respectively.
基金financially supported by Beijing Natural Science Foundation (No. 2142037)
文摘Mn-Cu alloys could exhibit high damping ability and excellent mechanical properties after proper heat treatment. In order to reduce the influence of impurity elements on damping capacity of Mn-Cu alloys, rare ele- ment cerium (Ce) was added into MnCuNiFe alloys. It is indicated that the contents of C, S and Si which have adverse effects on the damping capacity decrease and the grains are refined with the Ce content increasing. The microstructure of the MnCuNiFeCe alloy was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The damping ability (tane) of the alloy was characterized by dynamical mechanical analyzer (DMA). It is found that the damping ability (tane) retains a very high level which is all above 0.05 from the temperature of -50 to 75 ℃ with the addition of Ce element. It is expected that the Ce alloying MnCuNiFe alloy with refined grains could find wide applications in the field of industry.