Research on Several Factors Affecting the Test of Thermal Expansion Coefficient of Glass Materials

Accurate measurement of glass transition temperature (Tg) and coefficient of thermal expansion (CTE) is of great significance in guiding the use and process performance of the materials. This manuscript measures the CTE and Tg of samples by the thermal expansion method and systematically researches the measurement factors affecting the Tg and the CTE, including the shape and size of the samples, the starting furnace temperature and the heat treatment process. The study shows that the sample shape and size, the starting furnace temperature and the heat treatment process all have an effect on the test results. At the same time, the placement of the sample and the data processing method will also make the test results deviate from the real value. Therefore, in order to accurately assess the thermal properties of the material, the size of the sample is specified to be 6 mm in diameter and 50 mm in length, while the initial temperature of the furnace during the CTE test should be lower than 35 degrees C. In addition, test samples of the same glass grade should undergo the same heat treatment process to ensure the accuracy of the test results.