Dynamic stiffness-based test systems for viscoelastic material characterization: Design considerations

Abstract

In this paper, several important design issues for viscoelastic material characterization test systems which utilize dynamic stiffness measurements are discussed. These discussions are focused on structural dynamics aspects of the design of these test systems. These test systems are used to experimentally obtain the complex modulus of viscoelastic solids such as rubber, plastics, etc. Various standards exist on dynamic stiffness-based viscoelastic material characterization test methods, which give general guidelines on possible test procedures, associated theory, and limitations of recommended test procedures. In these standards however, there is not enough guidance on how to design the details of such a test system, specifically the mechanical structure of the test system. In this paper, authors' past experiences on the structural design of such test systems are presented which may be utilized as design guidelines for design of similar test systems. Main design issues discussed in this paper include the effect of fixture compliance on the accuracy of calculated material data, frequency limitations, selection of actuators and sensors, and edge (Poisson's) effect considerations for material specimens. © The Society for Experimental Mechanics, Inc. 2012.