Thermogravimetric Analysis (TGA):
In this technique the change in sample weight is measured while the sample is heated at a
constant rate (or at constant temperature), under air (oxidative) or nitrogen (inert)
atmosphere. This technique is effective for quantitative analysis of thermal reactions that are
accompanied by mass changes, such as evaporation, decomposition, gas absorption,
desorption and dehydration. The following is the simplified diagram for the instrumentation:
The micro-balance plays a significant role, during measurement the change in sample mass
affects the equilibrium of the balance. This imbalance is fed back to a force coil, which
generates additional electromagnetic force to recover equilibrium. The amount of additional
electromagnetic force is proportional to the mass change. During the heating process the
temperature may go as high as 15000
C inside the furnace.
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