Dynamic modulus (sometimes complex modulus ) is the ratio of stress to strain under vibratory conditions (calculated from data obtained from either free or forced vibration tests, in shear, compression, or elongation). It is a property of materials.
[pdf] is studied using where an oscillatory force (stress) is applied to a material and the resulting displacement (strain) is measured. • In purely materials the stress and strain occur in , so that the response of one occurs simultaneously with the other.• In purely materials, there is a between stress and strain, where strain lags stress by a 90 degree ( ) phase lag.The storage modulus is the measure of the sample’s elastic behavior. The ratio of the loss to the storage is the tan delta and is often called damping. It is a measure of the energy dissipation of a material. Tools: Parallel plates (8 mm, 15 mm, 25 mm), Fiber and Film, Three-Point Bending.
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