Cohesion in alloys — fundamentals of a semi-empirical model

A semi-empirical model of alloy cohesion involving two material constants for each element is introduced by means of the physical ideas underlying the scheme. The resulting expressions for the heat of formation of binary alloys are presented and their applicability in various extreme situations is discussed. The model is shown to reproduce a vast amount of experimental information on the sign of heats of formation. Detailed comparison with experiment for particular classes of alloys will be presented in the sequels to this paper.