Round robin test on liquidus temperature of soda-lime-magnesia-silica float glass samples: A technical report of the ICG Technical Committee (TC 18) on Properties of Glass Forming Melts

摘要

The Technical Committee on Properties of Glass Forming Melts of the International Commission on Glass, carried out a round robin test on measuring the liquidus temperatures of three different industrially produced soda-lime-silica float glass samples. Experimental results from six laboratories have been compared and the experimentally derived data on liquidus temperatures and the primary crystals found have been interpreted with the aid of thermodynamic modeling results. The liquidus temperatures of the given typical float glass compositions were measured by some laboratories to be around 970°C and by some other laboratories to be around 1010°C. The deviation can be explained by kinetic limitations of formation of primary crystals during slow cooling of a silicate melt for some experimental procedures. Diopside, devitrite and β-wollastonite were the most frequently found crystalline compounds just below the liquidus temperature TL. Some laboratories applied large temperature gradients in their experimental procedures which may lead to an error in determining TL.