Correlation between the temperature dependence of yield stress and the nature of solute distribution in Cu-Ni solid solutions

Nature of solute distribution in copper single crystals alloyed with 0-100 at.% Ni has been investigated via temperature dependence of the yield stress. The composition-property diagram developed and interpreted in terms of the kink-pair nucleation model of flow stress in solid-solution crystals shows that the solute distribution is statistically random in Cu-Ni single crystals with solute concentration c ≤ 14 at.% Ni, and is non-random for c between 14 and 50 at.% Ni. Similarly, the solute distribution is statistically random in Ni-Cu single crystals with c ≤ 20 at.% Cu, and deviation from statistically random distribution of solute occurs for all other values of c up to 50 at.% Cu.