Interfacial energy of solid In2Bi intermetallic phase in equilibrium with In–Bi eutectic liquid at 72 °C equilibrating temperature

A radial temperature gradient on the sample was established by heating from centre with a single heating wire and cooling the outside of sample at − 10 °C with a heating/refrigerating circulating bath containing an aqueous ethylene glycol solution. The equilibrated grain boundary groove shapes of solid In2Bi (In-33.2 at.% Bi) in equilibrium with In–Bi eutectic liquid (In-22 at.% Bi) were observed from quenched sample at 72 °C. Gibbs–Thomson coefficient and solid–liquid interfacial energy of solid In2Bi in equilibrium with In–Bi eutectic liquid have been determined to be (11.3 ± 0.6) × 10− 8 K m and (47.8 ± 4.8) × 10− 3 J m− 2 from the observed grain boundary groove shapes. The grain boundary energy of solid In2Bi phase has been calculated to be (92.8 ± 10.2) ×10− 3 J m− 2 by considering a force balance at the grain boundary grooves. The thermal conductivities of solid In solution (In-12.4 at.% Bi), solid In2Bi (In-33.2 at.% Bi ), the eutectic liquid phase (In-22 at.% Bi) and their ratio at 72 °C have also been measured with radial heat flow apparatus and Bridgman type growth apparatus.