The Enthalpies of Mixing of Liquid Ni-Sn-Zn Alloys

Abstract

The partial and integral enthalpies of mixing of liquid ternary Ni-Sn-Zn alloys were determined. The system was investigated along two sections xNi/xSn ≈ 1:9, xNi/xSn ≈ 1:6 at 1073 K and along two sections xSn/xZn ≈ 9:1, xSn/xZn ≈ 4:1 at 873 K. The integral enthalpy of mixing at each temperature is described using the Redlich-Kister-Muggianu model for substitutional ternary solutions. In addition, the experimental results were compared with data calculated according to the Toop extrapolation model. The minimum integral enthalpy of approx. −20000 J mol-1 corresponds to the minimum in the constituent binary Ni-Sn system, the maximum of approx. 3000 J mol-1 is equal to the maximum in the binary Sn-Zn system.

Enthalpy of Mixing of Ternary Li-Pb-Sb Alloys

“…Because there is no phase diagram of the Li-Pb-Sb system it is not possible to say what the range of homogenous liquid at 923 K should be. Calorimetric measurements make it possible to detect liquidus limit, based on kinks of integral enthalpies and discontinuity of partial enthalpies with a concentration of added component, [14] accompanying crossing from homogenous liquid into two-phase concentration range. It helps if the data points are dense (concentration change between the points is small) otherwise any change of trend in integral enthalpies can go unnoticed.…”