Defective and Good Bearings
Thermal analysis comprises a group of techniques in which a physical property of a substance is measured as a function of temperature whilst the substance is subjected to a controlled temperature program (ICTAC definition of thermal analysis).
Where is thermal analysis used?
Quality control, R&D and failure analysis, are areas to which thermal analysis makes a significant contribution. For example, knowledge of melting and crystallization behavior is important for identifying materials in the plastics industry.
The food, pharmaceutical and cosmetic industries have many common thermal analysis applications, including the investigation of polymorphism: the property allowing a material to exhibit different crystalline forms. Such knowledge is particularly important for determining shelf life and storage conditions.
The main thermal analysis techniques and what they measure
The most important effects that can be analyzed by DSC are melting point, melting range and melting behavior. DSC is also used to determine the heat of fusion, glass transition, and oxidation stability.
TOA is useful for investigating polymorphic transitions, as well as for separating overlapping effects such as melting and decomposition.
TGA measures mass changes. The main applications of TGA are content determination, thermal stability, decomposition kinetics, and composition analysis.
TMA is normally used to study the expansion, softening or shrinkage of materials and the glass transition. Its unique application is the determination of the Coefficient of Thermal expansion, or CTE.
DMA is used to measure the mechanical behavior and properties of materials. This includes the modulus and damping behavior. It is the most sensitive method for measuring and characterizing glass transitions, Tg and sub-Tg relaxations, in materials.
Thu Apr 30 2020 16:00 +0200 [ English ]