Abstract
The miscibility gap in the liquid Fe-Sn system has been determined by a Knudsen-cell mass spectrometric combination. The limits of miscibility gap could be determined in situ by this technique. The determination was performed for the composition range 10.1 to 89.2 at%Sn and for the temperature range 1 200 to 1 600°C. The consolute point has been found to be located at about 1 495°C, and the limits of the miscibility gap have been determined at various temperaturs. The consolute point obtained in this study is lower than the literature values.
The activities of Fe and Sn at 1 550°C and 1 600°C were determined from the ion current ratios for various alloy compositions by the use of the modified Gibbs-Duhem equation. Though the activity curves exhibit large positive deviation from ideal behavior, the obtained activity curves change smoothly with the composition, which show no existance of the miscibility gap at these temperature.
