An investigation of the effect of temperature on viscosity and electrical conductivity of a copper enamel

The purpose of this study is the investigation of viscosity behavior and electrical conductivity of a copper enamel based on lead borosilicate. By using the dilatometeric measurements the characteristic temperatures of Tg (log η= 1012 Pa. s) and Ts (log η= 109. 25 Pa. s) obtained for the enamel (glaze) were found 478. 6 and 523. 9 °C respectively. Hot stage microscopy observations shows half sphere condition of the enamel around 800°C which correspond to a viscosity of log η= 103. 55 Pa. s. By using of these three obtained values and VFT equation، the dependency of viscosity verses temperature is investigated. Electrical conductivity of 10-8 Ω-1. cm-1 was calculated at 335°C for the enamel.