Experimental determination of solid-liquid interfacial energy for solid Sn in the Sn-Mg system

► The interface energy plays a key role in nucleation, phase transformations etc. ► GBG shapes for solid Sn in equilibrium with Sn-Mg eutectic liquid were observed. ► The thermal conductivity of the Sn-9 at.% Mg solid phase, κS has been measured. ► R of eutectic liquid phase to the eutectic solid phase has been determined. ► Γ, σSL and σGB from the observed grain boundary groove shapes were determined. ► Γ, σSL, σGB have been found to be 7.35 ± 0.36 × 10−8 Km, 136.41 ± 13.64 and 230.95 ± 25.40 mJ m−2.