Calculation of formation enthalpies and phase stability for Ru-Al alloys using an analytic embedded atom model

A simple analytic embedded atom model for hcp and fee metals is presented. Using such a model, the embedding functions, the potential functions and th e modifying functions for hcp Ru and fcc Al are derived. The thermodynamic data, such as the dilute-limit heats of solution, formation enthalpies of d isordered solid solutions and intermetallic compounds, for Ru-Al alloys are calculated. The results show that the calculations are comparable to the e xperimental data available and with the results calculated using the first principles and Miedema's theory. The calculations of the heats of formation of Al13Ru3, Al3Ru in the DO22 and DO3 structure type, Al2Ru in the C11b st ructure type and AlRu in the B2 structure type indicate that the trends in structural stability can be interpreted directly in terms of the formation energy. (C) 1999 Elsevier Science S.A. All rights reserved.