Abstract
Viscosity of binary Zn-Sn melt has been measured by the use of a oscillating viscometer in order to study the effect of compositional inhomogeneity in the cylindrical crucible and to obtain the reliable viscosity of the melt.
Gas bubbling device was introduced to homogenize the melt in the crucible. Apparent viscosities were measured for inhomogenized and homogenized melt, then the former showed lower value than the latter, and the inhomogeneity of the melt was considered to affect the viscosity measurement.
Viscosity of the melt decreases steeply with increasing Sn content up to the composition of about 50at%Sn, then maintains approximately constant value to pure Sn. Apparent activation energy of viscous flow also decreases with increasing Sn content. This kind of de-crease of the viscosity and the apparent activation energy of the mixture is considered to relate the volume expansion and the positive enthalpy of mixing.
