Mechanical testing of polymeric foams at low frequency

Porous materials, like plastic foams, are widely used for sound absorbing p urposes. This paper deals with the mechanical behaviour of polyurethane foa ms' skeleton. The complex elastic constants of open cell foams are measured at low frequency (from 1 Hz to 100 Hz). Quasi-static experimental configur ation and numerical inversion method are presented. In the case of isotropi c foams, measurements of the complex Young's modulus and Poisson's ratio ar e set out. Results can be directly used to predict the vibroacoustic behavi our of systems containing viscoelastic polyurethane foams. (C) 2000 Elsevie r Science Ltd. All rights reserved.