A new laser flash method for determining thermal conductivity of molten glasses

摘要

A new method has been developed for measuring thermal conductivity of molten glasses at high temperature. A sample is melted in a platinum crucible and heated to the desired temperature. A single pulse of laser beam (Nd-glass laser source) is flashed on the bottom of the platinum crucible and then the temperature decay of the same bottom surface of the crucible after pulse heating is measured by an InSb infrared ray detector. From the speed of temperature decay. both thermal conductivity and thermal diffusivity of glassy specimens are obtained. The reliability and usefulness of this method were tested by measuring successfully thermal diffusivities of some solid glass samples at temperature between 773 K and 1673 K.