Characterization of vibrational mechanical properties of polyurethane foam

Abstract

Polyurethane foam (PU) is widely used in numerous comfort applications such as automotive seat cushioning and mattresses. The present paper is devoted to describe experimental techniques and identification of dynamic properties of thin flexible polyurethane foam used in automotive seats. In the experimental device, a free mass is mounted on a 0.1 m2 of different foams used in car upholstery. The foam is the only flexible component. The device is excited with an electrodynamic shaker with frequencies varying between 10 and 200 Hz. The response of foam samples to sweep sine excitation is analyzed for different excitation acceleration amplitude (1-2.5 mm s-2) and for different free masses. In order to answer the issue of replacement, different multilayer products and single foam samples have been characterized and comparisons have been carried out. The results of this study show interesting properties in terms of dynamic behavior of multilayer products when compared to the PU foams.