Solid—liquid phase equilibria in the sodium-rubidium alloy system

Abstract

Thermal methods were used to determine with high precision, the solid-liquid phase equilibria diagram for the sodium-rubidium system. The results differ greatly from those of earlier workers, especially near the eutectic composition where differences in melting points as large as 25 K occur. A search was made for possible intermetallic compounds (especially Na₂Rb). Neither slow temperature cycling in the temperature range where compound formation could occur nor extended periods of annealing just above the eutectic temperature produced any evidence for compound formation. A 2 : 1 (sodium to rubidium) sample was subjected to 60,000 atm pressure. Again, no evidence was obtained for solid compound formation.