The phase relations and thermodynamic stabillity of metastable phases in rapidly quenched Ag-Ge alloys have been studied by means of DTA, DSC and X-ray powder diffraction techniques. Solubillity of Ge in Ag is extended from 1.5 at% Ge to 8 at% Ge, when cooling speed of alloy is approximately 104 K/s. Except supersaturated solid solution of Ge in Ag and Ge, there also exists a metastable phase, which has the hexagonal close-packed structure (hep) with lattice parameters a=2.893±0.010 ?, c=4.720±0.010 ?, c/a=1.632. For 20 at% Ge alloy, the activation energy of hep phase transition and supersaturated solution desolvation are 93 kJ/mol and 102 kJ/mol respectively. The nature and transition mechanism of the metastable phases are discussed.

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In this paper, the relationship between composition and crystallization temperature of Fe-base amorphous alloys are investigated systematically. Among 95 Fe-base amorphous alloys, the crystallization temperatures of about 85% of them are in the range of 700-825 K, Tcr/Tm≈1/2 (0.42-0.62), and conform to Sakka's principle The crystallization temperature of Fe1-x Bx-ySiy is greater than that of Fe1-xBx and the later greater than that of Fe1-xBx-yPy in turn. Those mentioned above are discussed with reference to the composition, phase diagrams, machanism of the crystallization, diffusion and the relationship between the crystallization temperature and the average electronic concentration (e/a).

The phase diagrams of pseudo-binary systems LaNi5-NdNi5 and LaNi5-CeNi5, the aniso-tropy of grain sizes of actived LaNi5-NdNi5 samples, hydrogen absorption capacity and hydrogen desorption isotherms at 29℃ and influence of other phase on hydrogen absorption characteristics of LaNi5 have been investigated by means of X-ray diffraction and DTA, X-ray diffraction line broadening method, and second ways respectively.The variations of lattice parameters, unit cell volumes and atomic distances of actived and unactived samples were determined.The anisotropy of grain sizes of actived LaNi5-NdNi5 system, the difference of hydrogen absorption capacity and hydrogen absorption plateau pressures of RmNi5(Rm = misch-metal) were explained from structure viewpoint and our experimental results.

The temperature dependence of ionic conductivity, especially the ion transport property during pre-crystallization process in amorphous ionic conductor Li2B2O4 has been studied. When the temperature is lower than Tk(≈310℃), the ionic conduction obeys Arrhenius relation. Above the crystallization temperature Tc(≈411℃), the ion transport behaviour is dominated by the process in crystalline state. In the range Tkc, the ionic conductivity deviates from thermal excitation mechanism and is enhanced anomalously. This process is now called pre-crystallization process. It is found that the free volume model could be used to describe the ion transport properties. In pre-crystallization process there are two distinguishable steps. Below Tp(≈380℃) the ionic conductivity increase is due to the redistribution of free volume. While above Tp considerable enhancement of the ionic conductivity is caused by the in-terfacial effect between the crystallites and amorphous matrix because small amount of crystallites (less than 5%) were emerged. The pre-crystallization status of the amorphous could be remained at ambient condition by quenching the specimen to room temperature. Therefore it is possible to prepare material with higher ionic conductivity than that of pure amorphous.