X-ray diffraction and DSC were used to investigate the crystallization behavior of amorphous Al 90Ni 5Ce 5 alloys at different quenching temperatures. All the amorphous Al 90Ni 5Ce 5 alloys quenched at different tempe...X-ray diffraction and DSC were used to investigate the crystallization behavior of amorphous Al 90Ni 5Ce 5 alloys at different quenching temperatures. All the amorphous Al 90Ni 5Ce 5 alloys quenched at different temperatures crystallize by two stages. The first stage corresponds to FCC Al phase precipitating from the amorphous matrix. The crystallization onset temperature increases with increasing quenching temperature. The quenching temperature also influences the isothermal behaviors. At low quenching temperatures, the FCC Al precipitation is only through grain growth. At high quenching temperatures, the FCC Al precipitation is through growth of quenched-in Al nuclei and nucleation and growth of new crystallites. The reason that the crystallization onset temperature varies with quenching temperature is likely as that the quenched-in Al nuclei decreases with increasing temperature.展开更多
The electrochemical properties of the as-cast CeMg11Ni and ball-milled CeMg11Ni+x% Ni（x=0, 50, 100 and 200, mass fraction） composites were investigated. The results show that homogeneous amorphous phase of CeMg11Ni+...The electrochemical properties of the as-cast CeMg11Ni and ball-milled CeMg11Ni+x% Ni（x=0, 50, 100 and 200, mass fraction） composites were investigated. The results show that homogeneous amorphous phase of CeMg11Ni+x% Ni composite can be obtained by ball-milling, and discharge capacity of the ball-milled CeMg11Ni+x% Ni composites differs greatly depending on the amount of Ni introduced during milling. The CeMg11Ni+200% Ni composite after 90 h ball-milling was found to exhibit a large discharge capacity of about 1 012 mAh/g at 303 K, and it also shows better charge-discharge cycling stability than those with lower Ni content. This remarkable improvement in electrochemical properties of the ball-milled composites seems to be attributed to the formation of an （amorphous） composite as well as the improvement of the surface state of the ball-milled particles.展开更多
文摘X-ray diffraction and DSC were used to investigate the crystallization behavior of amorphous Al 90Ni 5Ce 5 alloys at different quenching temperatures. All the amorphous Al 90Ni 5Ce 5 alloys quenched at different temperatures crystallize by two stages. The first stage corresponds to FCC Al phase precipitating from the amorphous matrix. The crystallization onset temperature increases with increasing quenching temperature. The quenching temperature also influences the isothermal behaviors. At low quenching temperatures, the FCC Al precipitation is only through grain growth. At high quenching temperatures, the FCC Al precipitation is through growth of quenched-in Al nuclei and nucleation and growth of new crystallites. The reason that the crystallization onset temperature varies with quenching temperature is likely as that the quenched-in Al nuclei decreases with increasing temperature.
基金Project (TG2000026406) supported by the National Basic Research Development Program of China Project (50471042)supported by the National Natural Science Foundation of China
文摘The electrochemical properties of the as-cast CeMg11Ni and ball-milled CeMg11Ni+x% Ni（x=0, 50, 100 and 200, mass fraction） composites were investigated. The results show that homogeneous amorphous phase of CeMg11Ni+x% Ni composite can be obtained by ball-milling, and discharge capacity of the ball-milled CeMg11Ni+x% Ni composites differs greatly depending on the amount of Ni introduced during milling. The CeMg11Ni+200% Ni composite after 90 h ball-milling was found to exhibit a large discharge capacity of about 1 012 mAh/g at 303 K, and it also shows better charge-discharge cycling stability than those with lower Ni content. This remarkable improvement in electrochemical properties of the ball-milled composites seems to be attributed to the formation of an （amorphous） composite as well as the improvement of the surface state of the ball-milled particles.
