Abstract
The weight reduction in vehicles without decreasing their safety is an important subject in manufacturing automobiles to improve the fuel efficiency and eventually to reduce the environmental pollution. To use high-stiffness urethane foam is one of the possible solutions to improve the body stiffness and the energy absorption of the vehicle. Therefore it is important to clarify the consolidation condition of the urethane foam under multi-axial loading conditions. Compaction properties of the uretahne foams were examined through both uniaxial compression and 3-dimentional compression tests by the equipment of which one shown later. From the results,we identified yield criterion of urethane foam by the constitutive equation proposed by using Oyane & Shima (1976) for compressible materials.
