Differential Thermal Analysis – A Complete Overview

What is Differential Thermal Analysis actually? It helps in detection of absorption or release of heat in materials, when they are either cooled or heated. It is a general phenomenon that a material goes through physical as well as chemical changes when either heated or cooled. DTA helps in detecting these changes, which is associated with the amount of heat absorbed or released. This information is important to understand the thermal properties of different materials. DTA is used by analysts for analyzing certain properties like: • glass transition temperaturern• chemical reactionsrn• crystalline phase changesrn• decomposition of glass batch materials The instrument’s temperature range remains anywhere between ambient and 1000°C. Is this Analysis Helpful? How? This unique method of analysis provides more information on a detailed way on the properties like: a) Identification of the transition temperature of glassrnb) Bulk crystallizationrnc) Liquidus temperaturernd) Other minor crystalline phase It has been empirically found out that DTA technique is far better than dilatometry. A company that offers thermal analysis software should also give the following services: i. The turnaround period should not be long. It should be fast. ii. Quick and efficient data interpretation should be done. iii. Comprehensive analysis of various kinds of materials such as polymers, ceramics and glasses are there. Other Services by a Company providing DTA It has been found out that a company that offers thermal analysis software provides other related services too and they are mentioned below: Dilatometry – This process of analysis helps in measuring and analyzing glass transition values as well as thermal expansion. Liquidus Temperature – This process helps in analyzing behavioral aspects of ceramic and glass crystallization. rnLittleton Softening Point – This helps in analysis of ASTM standard method C338. High Temperature Viscosity – This helps in the analysis of viscosity-temperature curve measurement High Temperature Electrical Measurements - This helps in the analysis of high temperature resistivity Thermal Analysis – Discussed in Details Three kinds of analysis are there and they are: 1. Thermogravimetric or TG Analysis 2. Differential Thermal Analysis (DTA) rn3. Differential Scanning Calorimetry (DSC) However, in case of DSC (Differential Scanning Calorimetry), instead of temperature difference energy difference is considered. In case of Thermogravimetry (TG), sample mass is measured with respect to increase in temperature. It helps in understanding and studying decomposition reactions and at the same time determining organic content, carbonate, and water. Pros and Cons There are many advantages of Differential Thermal Analysis . Some of the most glaring ones are mentioned below: 1. Even at very high temperature, the instruments can be used 2. The instruments that are used have highly sensitive features 3. Reaction or transition temperatures can be determined accurately While we are discussing about the several benefits, the article would be incomplete if the disadvantages of the thermal analysis software are not determined. Below mentioned are some of the disadvantages mentioned: 1. Reaction or transition estimations is only 20% to 50% DTA 2. Uncertainty in heats of fusion What is the exact process followed in the DTA Process?rnLet us describe the process in which they are performed:rna) Two materials are subjected to identical amount of heat, where one is an inert reference and the other is a sample. rnb) Now, the difference of temperature between these two materials is measured. rnThis is the exact process that is followed in differential thermal analysis.