Solid-liquid interfacial energy of neopentylglycol solid solution in equilibrium with neopentylglycol-(D) camphor eutectic liquid

摘要

The grain boundary groove shapes for equilibrated solid neopentylglycol (NPG) solution (NPG-3 mol% D-camphor) in equilibrium with the NPG-DC eutectic liquid (NPC-36.1 mol% D-camphor) have been directly observed using a horizontal linear temperature gradient apparatus. From the observed grain boundary groove shapes, the Gibbs-Thomson coefficient (r), solid-liquid interfacial energy (σsl) of NPG solid solution have been determined to be (7.5 ± 0.7) × 10~(-8) K m and (8.1 ± 1.2) × 10~(-3) J m~(-2), respectively. The Gibbs-Thomson coefficient versus T_mΩ~(1/3), where Ω is the volume per atom was also plotted by linear regression for some organic transparent materials and the average value of coefficient (t) for nonmetallic materials was obtained to be 0.32 from graph of the Gibbs-Thomson coefficient versus T_mΩ~(1/3). The grain boundary energy of solid NPG solution phase has been determined to be (14.6 ± 2.3) × 10~(-3)Jm~(-2) from the observed grain boundary groove shapes. The ratio of thermal conductivity of equilibrated eutectic liquid to thermal conductivity of solid NPG solution was also measured to be 0.80.