A method for material characterization of sealing system elastomers using sound transmission loss measurements

The acoustic properties of sealing systems are essential for the noise control of new-generation vehicles and closure systems. Accurate characterization of the elastic elastomer properties is essential to perform acoustic analyses; however, this characterization is challenging due to the sophisticated behavior of the elastomers under certain conditions. There are several methods to obtain the elastic properties of elastomers, including thermomechanical, dynamic and modal techniques. This study proposes an alternative method for elastic characterization utilizing impedance tube-based sound transmission loss measurements. The surface vibration of the elastomer samples under the harmonic acoustic load is calculated using plate and membrane theory. Reverse characterization is performed using the relation between the partition impedance and surface integral on a one-dimensional plane wave field. This method may provide better accuracy for acoustic investigations since the same physical conditions are satisfied with the theoretical assumptions during the characterization tests. Finally, deviations from the corresponding theoretical models are explained, and empirical coefficients are derived based on the experimental results.