Determination of the two-melt phase boundary and study of the binary diffusion in liquid Bi–Ga system with a miscibility gap
| Autor: | R.A Khairulin, A.L Sorokin, S.V Stankus |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Binodal
Arrhenius equation Phase boundary Spinodal decomposition Chemistry Thermodynamics Activation energy Atmospheric temperature range Condensed Matter Physics Electronic Optical and Magnetic Materials symbols.namesake Critical point (thermodynamics) Materials Chemistry Ceramics and Composites symbols Critical exponent |
| Zdroj: | Journal of Non-Crystalline Solids. 297:120-130 |
| ISSN: | 0022-3093 |
| DOI: | 10.1016/s0022-3093(01)00927-9 |
| Popis: | New data on the shape of the two-melt phase boundary of the bismuth–gallium system with a miscibility gap have been obtained by a γ-ray attenuation technique. According to the measurements the coordinates of the critical point of the liquid–liquid coexistence curve are: critical temperature TC=532.3±1.5 K; critical composition NC=29.5±0.3 at.% Bi. In an extended range around TC the critical exponent β of the coexistence curve equals 0.310±0.005, which agrees closely with non-classical value calculated by the method of high-temperature series expansions. Kinetics of homogenisation of the Bi–Ga melt of near-critical composition have been investigated over the temperature range from 570 to 1225 K using the same technique. The temperature dependence of the coefficient of binary diffusion D derived from these measurement has been found to obey the Arrhenius equation: D(T)=1.67×10 −3 exp [−27175/RT], cm 2 s −1 , for the concentration range 20–40 at.% Bi. |
| Databáze: | OpenAIRE |
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