Calculated mixing enthalpies of 11 IIB-IVB and IIB-VB binary alloy systems using a subregular model

There have been no theoretical calculations of the mixing enthalpies for group B metal alloy systems using the famous Miedema theory or from first principles. Therefore such systematic calculations for the 11 group IIB?IVB and IIB?VB binary alloy systems are performed for the first time using a subregular model. The results show that the agreement between the calculations and experimental data is pretty good and could be accepted from the theoretical or experimental points of view. It can be concluded from the results that the subregular model can be used for calculating the mixing enthalpies of the group B alloy systems, at least for the IIB?IVB and IIB?VB alloy systems.

Phase relations in the system PbS-PbSe-PbTe

Phase relations in the system PbS-PbSe-PbTe were investigated in the temperature range between 1150 and 300°C. There is a complete solid solution series along the join PbS-PbSe, whereas miscibility gaps exist below ∼ 350°C and 805°C along joins PbSe-PbTe and PbS-PbTe, respectively. Both gaps extend into the ternary system, and the range of the gap between PbS and PbTe reduces in size with temperature as well as Se-content.By using the subregular model of mixing (Ganguly and Saxena, 1987), mixing energetics and activity composition relations of PbX were derived. The temperature-dependence of the interaction parameters was calculated to be 5057.6 − 1.7T, 9605.2 − 4.4T, 3933.2 − 3.1T (T < 500°C), 6410.3 − 6.35T (T < 500°C) 1649 − 0.26T, 1594.6 − 0.2T, and 12906.3 − 17.3T for WWSte, WTeS, WSeTe, WTeSe, WSSe, WSeS, and WSSeTe, respectively. A critical temperature along the join PbS-PbSe at ∼ 100°C was obtained from interaction parameter calculation, which suggests the separation of the PbS-PbSe series.Correlation of solid-solution ranges established in this study with natural occurrences was made.