Liquidus temperature

The liquidus temperature (TL or Tliq) is the temperature above which no crystals can exist - above this temperature the melt should be homogenous. Prolonged heat treatment of glass can lead to crystallisation if the temperature is not properly controlled.

A temperature gradient furnace is used with glass placed in a platinum or ceramic boat and held for the required time. Test times are tailored to the specific sample and may vary from several hours to several days. Temperature profile throughout the furnace is monitored so that on removal and cooling the temperature profile across the sample is known.

Observation of the sample by polarised-light optical microscopy allows determination of the liquidus temperature of the glass and identification of the primary crystalline phase if required.

Measurements of liquidus temperature have regularly been made for many of our customers. These may be problems related to crystal formation during changes in production, or in the fibreglass industry, where the process is interrupted by fibre breakage caused devitrification in glass.

• Liquidus temperature;
• Primary phase Identification;
• Composition development and modification;
• Rapid turnaround services;
• Training courses specifically for liquidus temperature determination.

Please contact us, or make an enquiry using the form above, if you have any bespoke requirements, require further information, or would like a quote for analysis.