1981 Volume 67 Issue 11 Pages 1952-1961
The activities, interaction parameter and partial molar heats of solution in the Fe-Sn system at 1 550 and 1 600°C and the interaction parameter in the Fe-Sn-Cu system at 1 560-1 610°C have been determined by use of the combination of a mass spectrometer and a Knudsen-cell. The liquid miscibility gap in the Fe-Sn system is not observed in this study in the temperature range from 1 550 to 1 610°C. The ion current ratios for the alloy components are measured from 1 200 to 1 610°C, the concentration of tin Nsnbeing kept 0.50, and the temperature of critical mixing is determined to be about 1 505°C.
The obtained thermodynamic quantities are as follows:
The Fe-Sn system;
1 600°C:γ°Sn=2.58, γ°Fe=4.86
1 550°C:γ°Sn=2.68, γ°Fe=5.00
1 600°C:εSnSn=-0.29±0.06
The Fe-Sn-Cu system;
1 560-1 610°C:εCuSn=-42 500/T+16.27(±0.04)