Mechanical Experiments And Finite Element Simulation Of Rigid Polyurethane Foam In The Car

Side impact causes serious injury to the occupants due to the near distance and small buffer space between collision location and occupants. Side impact has become one of the focuses in automotive safety field. Rigid polyurethane foam has become one of the important filled materials in automotive interior and exterior assembly. Experiments are done to study the mechanical properties of rigid polyurethane foam, and the experimental data are used to verificate the foam models embedded in commercial finite element software LS-DYNA.The main works to be carried out are given as the following:(1) In uniaxial compression test, the platform stress, Young’s modulus, energy absorption and energy absorption efficiency of rigid polyurethane foam at different strain rates show strain rate sensitivity, and during the three stages of compression, rigid polyurethane foam exhibits different recovery characteristics(2) In the tensile test, rigid polyurethane foam shows fracture of brittle properties and tensile strength and elastic modulus increase with the strain rates, but the tensile strain at different strain rates behaves the opposite rule.(3) In the hydrostatic pressure test, Young’s modulus and platform stress of the rigid polyurethane foam are higher than uniaxial compression test’s; confining pressure test curve includes only two stages: the elastic stage and the peak back area stages, when the confining pressure exceeds a certain value(This article is 0.6MPa), the mechanical curves of rigid polyurethane foam exhibits randomness, which is no law at all(4) when Mat83, Mat163, Mat75 are taken to simulate the foam which are filled in the hip’s position, all are in line with the requirements of the industry that before 24 mm space collapse, the reaction force of head impactor is less than 3000 N, but compared with the experimental curve, Mat75 material model simulation’s result is more similar to experimental curve; within 24 mm compressional space, energy absorbing of rigid polyurethane foam has reached 46.7% of the total energy...