Dilatometry & Thermal Expansion (CTE) Testing Services

Dilatometry is a method for characterizing dimensional changes of a material as a function of temperature. The measurement may be performed across a temperature range (e.g. from 800° to 1600°C), or a specific controlled temperature program to mimic industrial processes, firing regimes, or a material’s operating environment. The coefficient of thermal expansion is defined as the degree of expansion divided by the change in temperature.

A precise understanding of thermal expansion behaviour provides crucial insight into firing processes, the influence of additives, reaction kinetics and other important aspects of how materials respond to environmental changes. Typical applications include: the determination of the coefficient of thermal expansion, annealing studies, determination of glass transition point, softening point, densification, kinetics and sintering studies.

High Precision Dilatometer

TAL offers dilatometry measurement services using our inhouse developed Ctherm Dil system. A sample is placed inside a retractable, tubular furnace. A spring-loaded pushrod is positioned against the sample. The opposite end of the pushrod is connected to a linear variable displacement transducer (LVDT). The dimensional change of the sample resulting from the controlled temperature program is measured as the pushrod physically transmits the length change to the LVDT. The displacement is recorded in relation to the temperature recorded with a thermocouple located next to the sample. A calibration or correction curve is applied in compensating for the expansion of the sample holder and pushrod. We offer analysis of materials from room temperature to 1600 °C and under inert, oxidizing or ambient atmospheres.

Testing Capabilities

Standards

• ASTM E228 – Linear Thermal Expansion of Solid Materials With a Push-Rod Dilatometer