Dynamic Mechanical Analyzers (DMA) are commonly used to measure the dynamic properties of material samples (e.g. damping and stiffness) at different frequencies. In our material lab, a DMA is used to test samples of polymer thermo-sets employed for electronic packaging. To evaluate the mechanical reliability of chips, simulation of the fabrication process is required and thus knowing the material properties of the thermo-sets i of primordial relevance. The DMA currently used is designed to test soft materials such as rubber. Testing polymers, which might exhibit much higher stiffness, is challenging in such a setting. One important concern is that the dynamic stiffness of the subcomponents of the measuring column significantly influence the estimation of the dynamic stiffness of the sample itself In particular, the clamping in place between the force and displacement sensors and the sample cannot always be considered as infinitely stiff or massless. In this work, we fit a discrete model on the measuring column based on dynamic identification of its subcomponents. The model indicates that, as such, the DMA is not capable of providing accurate measurements for material stiffer than rubber. However, an accurate model of the measuring column could be used to extract the actual sample stiffness based on the DMA measurements.
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