Thermodynamic analysis of Al-Zn alloys from calorimetric measurements

The activities and activity coefficients of Al and Zn in liquid Al-Zn alloys covering the entire composition range were determined at 720°C (993° K) in an iso-peribol calorimeter similar to the one used by Oelsen and his associates. The results are in reasonable agreement with the previous values determined by radioactive tracer dew point method, electromotive force measurement method and isopiestic method. The other thermodynamic parameters like the integral molar enthalpy (HM) and its partial quantities, the integral molar entropy (SM) and formation potential (FM/T of Al-Zn alloys were also determined at 720°C (993°K) (Dr. A.K. Nayak, Scientist, National Metallurgical Laboratory)