Damping test process analysis

Table 5.3 lists the principal experimental methods used in dynamic mechanical testing. Of the experiments considered below, the thermal scan mode (method 1) is the technique most commonly used by thermal analysts. Here typical applications in quality control or processing look for differences in material batches, thermal history, different grades, reactivity, and other characteristics. The stepped isotherm (or step isothermal) experiment (method 2) is used mainly in studies involving detailed mechanical property determination for structural analysis, vibration damping applications, and for determining time-temperature superposition master curves. Method 3 (fast scan or single isotherm) is application specific. 

Tests of linear, quadratic, and higher order polynomials have been applied to a wide variety of tabulated data available from the literature. A multiple linear regression model has been found to yield a better fit than simple polynomials in many cases. Intersection points yield transition temperatures or pressures, as the case may be. Examples of melt viscosity data will be discussed in this paper. Residuals analysis and the magnitude of the calculated standard error are used as descriptors of the goodness of fit for the statistical tests. The judicious use of derivative treatments on dielectric and dynamic mechanical relaxation data to enhance weak liquid state damping processes is also presented. 

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