Design and Fabrication of Differential Thermal Analyser for Thermal Characterization of Materials

Design and Fabrication of Differential Thermal Analyser for Thermal Characterization of Materials

Thermal analysis techniques are widely used in both industrial and scientific domains to understand the changes in structural and chemical composition of materials. The structural and chemical composition of most of the materials undergoes changes when heated. Using various thermal analysis techniques such changes are monitored in various atmospheres of interest. Through these analytical experimental techniques the physical properties of the substance can be studied as a function of temperature. These techniques can be used to characterize, qualitatively and quantitatively a huge range of materials over a substantial temperature range. Results from the thermal analysis instruments can be obtained quickly and henceforth it has wide variety of applications. These thermal methods find widespread use for both quality control and research applications on polymers, pharmaceutical preparations, clay, minerals, metals and alloys. Differential thermal analysis is one of the thermal analysis methods, which records the difference in temperature (??T) between a substance and an inert reference material as a function of furnace temperature or time. Any transformation ?? change in specific heat or an enthalpy of transition ?? can be detected by Differential Thermal Analyser (DTA). The automated DTA is available readily from various manufacturers but it is expensive. Therefore researchers usually prefer to design and build their own instruments as per the individual requirements of experiments under various specialized conditions. Furnace, sample holder, controlled heating source, low noise-high gain amplifier and differential recorder are the main units of a differential thermal analyser. In the present work, we have made an attempt to design and fabricate a low cost differential thermal analyser for the thermal analysis of materials.

M V Muthamma

Department of Physics