Experimental measurements through ultrasounds for viscoelasticity analysis

Among the different methodologies useful to determinate polymers viscoelastic properties in literature, it is possible to find some different techniques based on the ultrasounds pulse-echo methods which show several limits in the properties estimation of the tested materials. In this scenario, the proposed manuscript focuses on an innovative non-destructive technique of viscoelastic materials by means of ultrasounds, which could be suitably employed on polymers. The developed procedure is aimed to evaluate the material response in terms of loss factor within different temperatures and induced excitation frequencies. To carry out the viscoelasticity analysis through ultrasounds, a bench has been set up and the data acquisition has been performed by means of the pulse-echo method on three different tires tread specimens and, then, a post-process algorithm has been implemented in order to determine the viscoelastic behavior in terms of loss factor. The comparison of the achieved results with the temperature sweep master curves, which were determined by means of standard Dynamic Mechanical Analysis (D.M.A.) testing on the same polymers, has provided an indication of the goodness of the proposed procedure.