The phase boundaries in binary alloys, part 1: the equilibrium between liquid and solid phases

The thermodynamic theory of the melting-point and freezing-point curves, in the α solid-solution region, of binary alloys is briefly considered. It is shown that the van 't Hoff relation should be applicable to these alloys, and its validity, for sufficiently dilute solutions is verified by comparison with experiment. It is shown from experiment that the change in the latent heat when small quantities of nickel,zinc,gallium or germanium are dissolved in copper is proportional to the electron: atom ratio. Similar results are obtained for cadmium, indium or tin dissolved in silver. A qualitative theory is proposed to account for these effects.