Thermomechanical analysis (TMA)

Thermo-mechanical analysis includes measuring a specific deformation mode such as flexure or thermal expansion under a change in temperature. Thermo-mechanical analysis (TMA) can be used to identify the glass transition temperature, . For flexural TMA testing, a rectangular specimen is loaded in bending and the dimensional change is measured as a function of temperature. As for DSC, software is available to calculate based on the curves. A disadvantage of TMA testing for composites is that overall stiffness is dominated by the stiffness of the reinforcing fibres. This makes detection of the property charges, occurring through the glass transition of the softer matrix material, difficult to distinguish. TMA using a penetration technique overcomes this problem provided the probe used for measuring the expansion is not too close to, or touching, a fibre.