An instrument design concept to minimize creep ringing during step-stress experiments with viscoelastic materials

作者：Chan Hubert K^*; Mohraz Ali

来源：Applied Physics Letters, 2014, 105(3): 034102.

DOI：10.1063/1.4890739

A common observation in step-stress rheological measurements on viscoelastic materials is the prevalence of early stage strain oscillations, which result from a coupling between the measuring system's inertia and the sample's elasticity. This phenomenon, conventionally known as creep ringing, is generally undesirable because it can mask the material's inherent microstructural response to an external stress. In this work, we show how this undesirable effect can be dramatically suppressed in a custom-built shear cell designed for rheo-optical experiments. Using a combined theoretical/experimental approach, we demonstrate that the suppression of creep ringing is due to a low moment of inertia for the measuring system and a unique design concept, in which the torque source is coupled to the sample through a viscous transfer fluid.

• 出版日期2014-7-21