Interfacial Energy of Solid Bismuth in Equilibrium with Bi-In Eutectic Liquid at 109.5℃ Equilibrating Temperature

• Published in: Metals and materials international Vol. 14; no. 2; pp. 177 - 187
• Main Authors: Yavuz Ocak, Sezen Akbulut, Necmettin Marasli, Kazlm Keslioglu, Ugur Boyuk, Hasan Kaya, Emin Cadirli
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 01.04.2008
• Subjects: bismuth based alloy; crystal growth; grain boundary energy; interfacial energy; thermal conductivity
• ISSN: 1598-9623; 2005-4149

The interfacial energy of solid bismuth (Bi) in equilibrium with Bi-In eutectic liquid was determined for the equilibrating temperature of 109.5℃. A radial temperature gradient on the sample was established by heating it from the center with a single heating wire and cooling the outside of the sample at -10℃ with a heating/refrigerating circulating bath containing an aqueous ethylene glycol solution. The equilibrated grain boundary groove shapes of solid Bi in equilibrium with Bi In eutectic liquid (Bi- 47.3 at.%In) were observed from a sample quenched at 109.5℃. The Gibbs-Thomson coefficient and the solid-liquid interfacial energy of the solid Bi in equilibrium with Bi In eutectic liquid were determined to be (8.4 ± 0.4) × 10-8Km and (54.0 ± 5.4) × 10-3 Jm-2 from the observed grain boundary groove shapes. The grain boundary energy of the solid Bi phase was calculated to be (105.5 ± 11.6) × 10 -3 J m -2 by considering a force balance at the grain boundary grooves. The thermal conductivities of Bi-47.3 at.%In eutectic liquid phase and the solid Bi-47.3 at.%In phase and their ratio at 109.5℃ were measured with a radial heat flow apparatus and a Bridgman type growth apparatus.