58 energy dissipation, intensive construction, hyperelastic, foam Jerzy OSIŃSKI * , Przemyslaw RUMIANEK ** THE IDENTIFICATION PROPERTIES OF POROUS FOAM Abstract The aim of this work is to develop methods of describing the properties of such materials based on knowledge of: basic materials, technologies (gas pressure formed during foaming) using the theory of hyperplastic materials. The resulting description can be used for the applicability of hyperelastic models, and therefore in the whole range of deformation of the polymer-based composites and elastic composites of metals (not included plasticity). Thesis presents analysis methods of hyperelastic materials using Finite Elements Method. Using FEM it is possible to verify used material, define materials models and show effectiveness of designed component without performing expensive impact tests. Presented methods and applications of the characteristics of hyperelastic materials and composites with the gas phase are used to determine the proper selection of parameters (material properties), increasing the opportunities for a proper assessment of the effectiveness of safety devices. 1. INTRODUCTION Porous polyurethane foams are widely used in the construction of motor vehicles in particular in the protective structures – systems and energy- dissipating units [5]. Used materials are foamed polypropylene, in the form of pressure, not interconnected granules. Process of static compression for the analyzed polymer foams was determined [11] with the energy absorption and energy dissipation efficiency. By using different sizes of granules elements we obtain different densities in the range of 25 g/dm³ to 220 g/dm³. The surface porosity and surface properties are dependent on the release of active ingredients and the process of formation. The analyzed foams have a high pore volume, mainly inside the macropores. Energy consuming structure is formed in the * Warsaw University of Technology, The Institute of Machine Design Fundamentals, 84 Narbutta Str., 02-524 Warsaw, Poland, jos@simr.pw.edu.pl ** Warsaw University of Technology, The Institute of Machine Design Fundamentals, 84 Narbutta Str., 02-524 Warsaw, Poland, przemyslaw.rumianek@gmail.com